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AMD's New Threadripper Chips Have a Hidden Fuse That Blows When Overclocking

82 points by webmaven 3y ago

DeathArrow 3y ago
I don't know if overclocking pays off much these days. The chips are already taken close to limits with factory settings, so there's not much overclocking potential unless you use extreme cooling. I fondly remember the Core 2 Duo days when I overclocked my CPU with more than 50% using the stock cooler. It's nice to 50% performance for free, particularly when you are poor. I even remember overclocking an old laptop with K6-II (those days laptop CPUs were socketed) by around 15%.
- dtx1 3y ago
  Overclocking these modern CPUs is usually just removing the powerlimit. They can clock themselves pretty close to the thermal limit anyway and little is gained in raw performance above that. But the Performance/Watt drops significantly when overclocking.
  - olavgg 3y ago
    I have a 10850k cpu, with a HUGE Be Quiet heatsink. Any heavy CPU workload will draw 300+watt, without any overclocking, the cpu will downclock, but not throttle around 100 Celsius. Overclocking has never been more dead than it is today. The days with old Celeron 300 or Core 2 Duo days with 50% + overclock speed are long gone. Today you will most like hit max temperature and cpu throttling.
    - dtx1 3y ago
      > the cpu will downclock, but not throttle around 100 Celsius. Downclocking is literally throttling. But there's like another 10% performance that can be unlocked if you'd go full custom watercooling.
      - automatic6131 3y ago
        >But there's like another 10% performance that can be unlocked if you'd go full custom watercooling. It's actually less than 10%. I'd say closer to around 5% - as a custom watercooling enthusiast. 2-3% gains going from a great dual tower air cooler to an All-in-One closed loop (but extra noise from the pump) and another 2-3% gains for a great CPU waterblock and thicker, denser radiators of custom watercooling (and least noise of all, assuming you choose an appropriate pump speed). 5% performance gains, and 500% price increase <:o)
  - kbar13 3y ago
    fine with that. for 99% of users it's great that factory settings allow the chip to run basically at max potential without having to be an expert in the complex web of acronyms/timings/voltages for overclocking
- nicolaslem 3y ago
  Undervolting (removing the safety margin put in place for binning) and removing power limits is where the gains are today. Ryzen 5000 could get some pretty nice multicore gains by undervolting using PBO2.
- consp 3y ago
  The days of creating a resistor bridge with a pencil to enable extra cores and altering the multiplier are long gone. I still remember pushing my duron with a massive aluminium block on top of it getting 100+mhz more out of it.
  - DeathArrow 3y ago
    I remember when you could enable cores in a GPU just by flashing a different firmware.
    - keep_reading 3y ago
      Wasn't there a time when you could flash a GeForce to a Quadro and you'd lose some performance in gaming but you gain floating point precision for rendering? Or was this a rumor?
- codeflo 3y ago
  One argument used to be that there's always manufacturing tolerances that you can exploit to your advantage. However, those tolerances were in many cases optimized out of the process by better binning -- if a particular CPU reliably worked at a higher clock speed, it would simply be sold at a higher speed. But also, whether a chip is actually stable at settings X or Y has become a lot harder to determine due to complexity: multicore architectures, frequency scaling and power management in general make it hard to predict how a chip will behave under real conditions. It has become unrealistic for a user to test all cores under all possible combinations of workloads. Consequently, and from anecdotal experience at least, many overclocked systems seem a lot less stable than their owners claim.
  - DeathArrow 3y ago
    >But also, whether a chip is actually stable at settings X or Y has become a lot harder to determine due to complexity There are many good software for stress testing CPUs and GPUs. Just run AIda64 or OCCP stress tests for a long time and you are good to go if no problems arise. If there are problems, you redo the settings and run the tests again.
    - codeflo 3y ago
      I think that's naive, or let's say oversimplified. There are too many cases where systems pass these tests and then fail in real-world scenarios, sometimes quickly. There's simply no way that a specific set of software routines can guarantee that a processor behaves in spec.
- chmod775 3y ago
  The most basic "overclocking" these days is actually undervolting. The clock speed you can leave to the chip. The undervolting makes the chip run cooler, which in turn means it can stay at higher frequencies longer.
  - DeathArrow 3y ago
    You need higher voltage to have a chip (CPU, GPU, RAM) stable at a higher frequency. Higher voltage means more heat, so you need better cooling.
    - jpgvm 3y ago
      This actually depends on silicon quality. The mainboard manufacturers generally configure the OOB CPU voltages higher than they need to be in anticipation of handling crappy silicon. If you have a higher binned CPU then you can reduce that voltage and still be stable at a given clock, the chip will then be able to boost higher because there will be more thermal headroom.
- paulmd 3y ago
  Frankly this is aimed more at XMP, where vendors routinely bump IMC voltage to get those swanky binned gaming kits onto the QVL. A ddr4-4800 kit obviously isn’t going to work on stock voltage with a memory controller rated at 3200, the gap is covered by increasing VCCIO and VCCSA a lot, and this results in quite a few chips with failed memory controllers over time. Also, on AMD there is an extremely widespread culture of overclocking the fabric which again, can result in degradation over time (progressively lower clocks at a given voltage, or instability at a fixed clock). People very much still believe in the fairy-tale of “24/7 safe” overclocking - obviously the manufacturer has every incentive to certify the chip as fast as it’ll go, they set the limit at the 24/7 safe point already, but the gains are so potent that people tell themselves whatever they need to hear. https://www.amd.com/en/legal/claims/gaming-details.html https://www.amd.com/en/legal/claims/gaming-details.html AMD and intel have been very very clear for a very long time that this is not covered by warranty (see AMD GD-106/GD-112) but people have low key continued to do it and warranty the CPUs when they fail, because there wasn’t a way for AMD and intel to tell. And to be fair - AMD and intel have often muddled the waters by using these numbers in their benchmarks etc. But there remains a general sense of “if you didn’t turn on XMP you didn’t do the build right” and “XMP can’t hurt anything as long as you don’t increase the voltages” despite this already being done automatically by the board. XMP absolutely does cause damage and I killed a 9900k with no other overclocking simply by enabling XMP on a fast kit. But consumers still don’t get the memo, they think it is only a problem if you instantly blow up the chip like the 7000 series at launch. XMP is widely viewed as safe and even something you're supposed to be doing. Electromigration happens very quickly at 7nm and 5nm nodes, and people are not used to it, and it’s low key also a thing on 14nm and 10nm class too. But it is already something that CPUs have to be designed around and designed to detect and monitor and tolerate as part of the boost algorithm (that stability margin is also headroom the boost algorithm wants to exploit), they devote an enormous amount of effort to electromigration already. And the mismatch between that public understanding of the problem and the reality is causing a lot of warranty claims. You can see from enterprise fleets that CPUs don’t normally fail, yet every enthusiast knows someone who had a chip die “even without overclocking! I just enabled XMP!”. Of the failed CPUs getting returned for warranty, probably a plurality are memory overclocking failures. And this is only going to continue to get worse over time - 2.5D and 3D packaging are both progressively even more sensitive due to thermals, and have tighter requirements for voltage stability since they need to talk to the other dies at very low voltages (especially across heterogeneous dies with different metal stacks/totally different processes etc). https://semiengineering.com/3d-ic-reliability-degrades-with-increasing-temperature/ https://semiengineering.com/3d-ic-reliability-degrades-with-... https://semiengineering.com/on-chip-power-distribution-modeling-becomes-essential-below-7nm/ https://semiengineering.com/on-chip-power-distribution-model...
andrewstuart 3y ago
Expensive.
throw310822 3y ago
For those who just read the title: the "fuse" doesn't stop the cpu from working, it's just a flag for AMD support to know that the chip has been overclocked and this might invalidate the warranty.
- actionfromafar 3y ago
  To me this is actually a reasonable thing for AMD to do. It still leaves me free to do whatever I want with my property.
  - machinekob 3y ago
    [flagged]
    - offices 3y ago
      If Nvidia/Apple/Intel used hardware fuses? Hahaha!
    - m_st 3y ago
      Apple has (had?) a water sensor in the iPhones to detect that the phone was in water. Didn't break anything, just signaled that there was water contact.
      - Zetobal 3y ago
        I tripped mine when I was in Vietnam... just because of the humidity.
    - weberer 3y ago
      I know Nvidia does the same thing in their Tegra chips. It stops you from downgrading to previous firmware versions on the Nintendo Switch.
    - jeffparsons 3y ago
      I kinda assumed that all the above companies would already be doing something similar. I want to live in a world with warranties, so if there's a non-privacy-violating way for companies to protect themselves a little bit from fraudulent warranty claims, why shouldn't they do it?
signa11 3y ago
apparently it does not void the warranty: https://www.tomshardware.com/pc-components/cpus/amd-says-overclocking-blows-hidden-fuses-on-ryzen-threadripper-7000-to-show-if-youve-overclocked-but-it-wont-automatically-void-your-cpus-warranty https://www.tomshardware.com/pc-components/cpus/amd-says-ove...
- burrish 3y ago
  It does not void the warranty, but the overclocking is permanent and any damage that happens when overclocked isn't managed by the warranty (if I read everything right)
- Dalewyn 3y ago
  AMD also says it will in one of their hidden footnotes at the bottom of a marketing page: >Overclocking and/or undervolting AMD processors and memory, including without limitation, altering clock frequencies / multipliers or memory timing / voltage, to operate outside of AMD’s published specifications will void any applicable AMD product warranty, even when enabled via AMD hardware and/or software. From: https://www.amd.com/en/technologies/expo https://www.amd.com/en/technologies/expo The moral of this story is overclocking is not for the naive nor the ignorant, and you must be willing to write off any hardware subjected to overclocking.
  - Narann 3y ago
    Does it means that CoreCtrl can blow the fuse when underclocking? I’m doing this to avoid my CPU push the fans when doing casual browsing.
sylware 3y ago
Ofc it is not voiding the warranty, since I would be not surprise it would blow even if people sincerely did not engage in overclocking.
- nicolaslem 3y ago
  Similar e-fuses are common for preventing downgrading firmware, especially on consoles. Nintendo was famously running out of e-fuses to blow on the Switch because of the many vulnerabilities the console had. Point being that these e-fuses don't blow up randomly by themselves.
  - sylware 3y ago
    Indeed, but trusting there is only one cause and it is always on user will is just abusive.
  - 127361 3y ago
    That already happened on Xilinx Zynq FPGAs, where an incorrect power supply sequence causes random writes to one of the internal buses, which overwrites various eFuses, even after they have been locked. https://support.xilinx.com/s/question/0D52E00006hpKdKSAU/zynq-arm-core-1-bricked-due-to-efuse-bit-corruption?language=en_US https://support.xilinx.com/s/question/0D52E00006hpKdKSAU/zyn... I understand burning eFuses is necessary during production, but having them blowable when the device is operating normally could be compared to building disposable devices. One logic or software error and the device can be bricked permanently. That is a ridiculous state of affairs. What about single event upsets or some EMI induced glitch causing eFuse corruption? The power for burning the important fuses should be off at all times during normal operation. And we can have a test pad to supply the VPP during production. In the case of the AMD processors, a separate bank of fuses can be used to store diagnostic data for warranty returns, if necessary. If those get corrupted somehow, the device won't malfunction. But the important ones should not be possible to program after manufacturing, no matter what happens to the logical state of the hardware, period.
esskay 3y ago
I see no problem with this. If you overclock and damage you obviously shouldn't be able to claim warranty. The only thing that isn't as black and white is how they know if an overclocked faulty chip is faulty because of the overclock, or something else.
bob1029 3y ago
The use cases for overclocked CPUs are dead to me. There are so many other dominating factors that it is almost pointless to worry about per core frequency. Memory bandwidth is probably a bigger constraint for many practical applications. Faster core clocks doesn't do anything to resolve that.
burrish 3y ago
I mean... is it really necessary to overclock a AMD Threadripper, for the price of this new Threadripper ($9,999) I wouldn't take the risk of overclocking it..
- account42 3y ago
  > I mean... is it really necessary to overclock a AMD Threadripper Yes? The main point of the Threadripper (especially non-PRO) is that you have a many-core CPU that can still run at high frequencies. Othervise EPYC (many-core) or Ryzen (high speeds) would be enough.
  - burrish 3y ago
    Ah I see thanks, but still for this generation of Threadripper, I would avoid overclocking it if it means having no warranty. Also shit move from AMD because even if you overclock with their software, the warranty still becomes void
- unregistereddev 3y ago
  It depends. If I'm an IT manager at Pixar and this is going in the workstation of my best and most productive animator, the price might not matter. If reducing the time s/he spends waiting on the computer means I can produce movies faster, I'll take risks to give them the best machine possible. If I'm a home freelancer staking my livelihood on this workstation, I'm not taking the risk.
account42 3y ago
Of all the CPUs I have had not a single one broke from use before they were replaced due to obsolescence and I definitely have been pushing them. How common is CPUs being permanently damaged from reasonable overclocking anyway, especially modern ones that have integrated sensors and clock themselves down automatically?
- bravetraveler 3y ago
  CPUs are still pretty durable but they can be a bit temperamental. With the smaller process sizes there's less voltage tolerance before degradation occurs. The X3D chips from AMD pack things supposedly pack the cache so tightly that it's easy to get into trouble A lot of chips burned out with something relatively mild like 1.3V on the SOC! That protection is fairly limited. There aren't enough sensors for everything that's heat sensitive. Reducing voltages/clock speeds also may not be enough to save all of those. Very long way to say: not that common... but decently. edit: As Paul mentions in a peer comment, this is largely due to the memory controller being moved onto the CPU.
- paulmd 3y ago
  anecdotally, probably at least 25% of enthusiasts have had a cpu that "randomly died" or "started getting unstable over time" even though they supposedly never overclocked it, and the leading cause there is memory controller degradation caused by XMP. I had a 9900K fail due to XMP, no other overclocking.
amelius 3y ago
Why don't they just put some thermal feedback system in it, making the chip inherently safe?
- kayodelycaon 3y ago
  Thermal throttling has been a thing for a long time.
  - bravetraveler 3y ago
    Also only partially effective! A chip that's: * on * idling * at room temperature ... is slowly degrading. This is only expedited by raising voltages when overclocking. Current passing through conductors wears them down. More current or heat means faster. What's more, there aren't enough sensors (or room to put them) for every heat-sensitive component.
blagie 3y ago
Speaking as an engineer, this is an essential feature. From AMD's language, and common sense, the thoughts on this impacting warranty are misguided. I suspect this is a normal feature designed for debugging. If I am AMD, and I e.g. receive 20,000 defective / failed chips returned from a bad run, or am sampling failures to just improve reliability, I want to know how those devices failed. If, what's failing, are overclocked chips, I probably do want to lock down chips, void the warranty, or similar. If what's failing is a distribution of chips representing real-world use, I want to address the defect. In either case, if doing an RCA to understand the defect, I want to know how the chip was used. Reporting of maximum temperature, voltage, overclocking, etc. (all the data HDD keep in SMART) is super-helpful for that sort of analysis. Also: Voiding warranty for overclockers would have been dumb. I've never overclocked, but for anyone here running a business: Vocal thought leaders are important to your brand. Overclocking may be out-of-spec, but if you want the word on the street to be that your chips are awesome, they had darned well be singing your praises. I've never overclocked, but I've cost both Google and AMD millions of dollars of business: * I used to do business with Google before they broke my personal account, wiped out data for a startup I was working with, and broke / discontinued several services I rely on. I'm well enough known that me going around saying "Don't build a business on Google" (and ditto for many other folks on HN) means that GCP is starting a 100 meter dash with Azure and AWS about a hundred extra meters back. * I bought an AMD GPU for machine learning since I liked open-source. It didn't work, and AMD discontinued support a few months after I bought it. AMD wouldn't provide warranty support for lack of suitability to advertised purpose. I learned my lesson, and tools I'm building (which will likely have broad-based adoption) don't support AMD. There are customers you want to treat like a restaurant treats a food critic. It's not about them being profitable directly, but they're super-important.
ouraf 3y ago
That's similar to the e-fuses cellphone manufacturers use to know when a phone was rooted and void warranty regardless of what caused the malfunction, right?
127361 3y ago
I really don't like the idea of having field-programmable OTP memories in microprocessors. This shouldn't be possible, there should be a physical VPP pin (as in MediaTek SoCs), if you don't supply power to this then no fuses are blowable. Otherwise we're going to have ransomware physically brick CPUs if you do not pay up on time. There's even worse possibilities, I think some hardware has ~1KB of executable OTP which can be programmed in that manner - so it may just be possible to implement some kind of backdoor that resides in the physical CPU. Maybe something only a state-level attacker could do. For example, it could prevent CPU side-channel mitigations from ever working, somehow, e.g. by repeatedly writing to a private internal register to stealthily keep the CPU vulnerable. And few would ever know about it, because it's hidden in an on-chip security processor. Personally I utterly hate all AMD chips which have a Platform Security Processor. Locking down your own property to prevent you from accessing it should be illegal. There is a full Trustronic Trusted Execution Environment running in there, on both GPU and CPUs, I believe. For example the TEE firmware blob for a radeon GPU on Linux is "/lib/firmware/amdgpu/psp_13_0_7_sos.bin", with "sos" meaning Secure Operating System. And some of these firmware files are encrypted, so you can't reverse engineer them. The moment some ARM SoC company such as Rockchip comes up with a chip that's within an order of magnitude in performance, then my AMD chip (EPYC) is going in the bin. After being smashed to pieces with a hammer, live on YouTube, with an explaination why. That might get AMD marketing to pay attention. Update: Ampere Altra CPUs have seperate power pins for blowing eFuses, you can find it in the public datasheet here[1], on page 55, the supply pins are EFUSE_MFG_VDDQ1P8 and EFUSE_PCP_VDDQ1P8. It says tie to GND if unneeded. Also they have a public datasheet for the chip. I wonder if we can buy unfused CPUs without secure boot enabled? Or is that the default state of the chip? Could someone design a simple and cheap open-source motherboard for one of these processors, it's only a matter of time before the chips start turning up on Ebay? We will need more documentation from Ampere than just the datasheet, of course. 1. https://uawartifacts.blob.core.windows.net/upload-files/Altra_Max_Rev_A1_DS_v1_15_20230809_b7cdce449e_424d129849.pdf https://uawartifacts.blob.core.windows.net/upload-files/Altr...
- CoastalCoder 3y ago
  I'm guessing that vulnerabilities tied to ongoing manufacturer control (CPUs, cars, Polish locomotives, etc.) will continue until a widespread attack turns public opinion. And I fear that even then, lobbyists and/or intelligence agencies will neuter any response. Shoot, now I'm just making myself depressed.
giardini 3y ago
Opening of a sci-fi novel: Chinese manufacturers embed a Trojan horse mechanism into chips and batteries. The mechanism, triggered remotely by predetermined signal, disables chips and causes batteries to short-circuit and explode.

82 points by webmaven 3y ago

I don't know if overclocking pays off much these days. The chips are already taken close to limits with factory settings, so there's not much overclocking potential unless you use extreme cooling. I fondly remember the Core 2 Duo days when I overclocked my CPU with more than 50% using the stock cooler. It's nice to 50% performance for free, particularly when you are poor. I even remember overclocking an old laptop with K6-II (those days laptop CPUs were socketed) by around 15%.

dtx1 3y ago
Overclocking these modern CPUs is usually just removing the powerlimit. They can clock themselves pretty close to the thermal limit anyway and little is gained in raw performance above that. But the Performance/Watt drops significantly when overclocking.
- olavgg 3y ago
  I have a 10850k cpu, with a HUGE Be Quiet heatsink. Any heavy CPU workload will draw 300+watt, without any overclocking, the cpu will downclock, but not throttle around 100 Celsius. Overclocking has never been more dead than it is today. The days with old Celeron 300 or Core 2 Duo days with 50% + overclock speed are long gone. Today you will most like hit max temperature and cpu throttling.
  - dtx1 3y ago
    > the cpu will downclock, but not throttle around 100 Celsius. Downclocking is literally throttling. But there's like another 10% performance that can be unlocked if you'd go full custom watercooling.
    - automatic6131 3y ago
      >But there's like another 10% performance that can be unlocked if you'd go full custom watercooling. It's actually less than 10%. I'd say closer to around 5% - as a custom watercooling enthusiast. 2-3% gains going from a great dual tower air cooler to an All-in-One closed loop (but extra noise from the pump) and another 2-3% gains for a great CPU waterblock and thicker, denser radiators of custom watercooling (and least noise of all, assuming you choose an appropriate pump speed). 5% performance gains, and 500% price increase <:o)
- kbar13 3y ago
  fine with that. for 99% of users it's great that factory settings allow the chip to run basically at max potential without having to be an expert in the complex web of acronyms/timings/voltages for overclocking
nicolaslem 3y ago
Undervolting (removing the safety margin put in place for binning) and removing power limits is where the gains are today. Ryzen 5000 could get some pretty nice multicore gains by undervolting using PBO2.
consp 3y ago
The days of creating a resistor bridge with a pencil to enable extra cores and altering the multiplier are long gone. I still remember pushing my duron with a massive aluminium block on top of it getting 100+mhz more out of it.
- DeathArrow 3y ago
  I remember when you could enable cores in a GPU just by flashing a different firmware.
  - keep_reading 3y ago
    Wasn't there a time when you could flash a GeForce to a Quadro and you'd lose some performance in gaming but you gain floating point precision for rendering? Or was this a rumor?
codeflo 3y ago
One argument used to be that there's always manufacturing tolerances that you can exploit to your advantage. However, those tolerances were in many cases optimized out of the process by better binning -- if a particular CPU reliably worked at a higher clock speed, it would simply be sold at a higher speed. But also, whether a chip is actually stable at settings X or Y has become a lot harder to determine due to complexity: multicore architectures, frequency scaling and power management in general make it hard to predict how a chip will behave under real conditions. It has become unrealistic for a user to test all cores under all possible combinations of workloads. Consequently, and from anecdotal experience at least, many overclocked systems seem a lot less stable than their owners claim.
- DeathArrow 3y ago
  >But also, whether a chip is actually stable at settings X or Y has become a lot harder to determine due to complexity There are many good software for stress testing CPUs and GPUs. Just run AIda64 or OCCP stress tests for a long time and you are good to go if no problems arise. If there are problems, you redo the settings and run the tests again.
  - codeflo 3y ago
    I think that's naive, or let's say oversimplified. There are too many cases where systems pass these tests and then fail in real-world scenarios, sometimes quickly. There's simply no way that a specific set of software routines can guarantee that a processor behaves in spec.
chmod775 3y ago
The most basic "overclocking" these days is actually undervolting. The clock speed you can leave to the chip. The undervolting makes the chip run cooler, which in turn means it can stay at higher frequencies longer.
- DeathArrow 3y ago
  You need higher voltage to have a chip (CPU, GPU, RAM) stable at a higher frequency. Higher voltage means more heat, so you need better cooling.
  - jpgvm 3y ago
    This actually depends on silicon quality. The mainboard manufacturers generally configure the OOB CPU voltages higher than they need to be in anticipation of handling crappy silicon. If you have a higher binned CPU then you can reduce that voltage and still be stable at a given clock, the chip will then be able to boost higher because there will be more thermal headroom.
paulmd 3y ago
Frankly this is aimed more at XMP, where vendors routinely bump IMC voltage to get those swanky binned gaming kits onto the QVL. A ddr4-4800 kit obviously isn’t going to work on stock voltage with a memory controller rated at 3200, the gap is covered by increasing VCCIO and VCCSA a lot, and this results in quite a few chips with failed memory controllers over time. Also, on AMD there is an extremely widespread culture of overclocking the fabric which again, can result in degradation over time (progressively lower clocks at a given voltage, or instability at a fixed clock). People very much still believe in the fairy-tale of “24/7 safe” overclocking - obviously the manufacturer has every incentive to certify the chip as fast as it’ll go, they set the limit at the 24/7 safe point already, but the gains are so potent that people tell themselves whatever they need to hear. https://www.amd.com/en/legal/claims/gaming-details.html https://www.amd.com/en/legal/claims/gaming-details.html AMD and intel have been very very clear for a very long time that this is not covered by warranty (see AMD GD-106/GD-112) but people have low key continued to do it and warranty the CPUs when they fail, because there wasn’t a way for AMD and intel to tell. And to be fair - AMD and intel have often muddled the waters by using these numbers in their benchmarks etc. But there remains a general sense of “if you didn’t turn on XMP you didn’t do the build right” and “XMP can’t hurt anything as long as you don’t increase the voltages” despite this already being done automatically by the board. XMP absolutely does cause damage and I killed a 9900k with no other overclocking simply by enabling XMP on a fast kit. But consumers still don’t get the memo, they think it is only a problem if you instantly blow up the chip like the 7000 series at launch. XMP is widely viewed as safe and even something you're supposed to be doing. Electromigration happens very quickly at 7nm and 5nm nodes, and people are not used to it, and it’s low key also a thing on 14nm and 10nm class too. But it is already something that CPUs have to be designed around and designed to detect and monitor and tolerate as part of the boost algorithm (that stability margin is also headroom the boost algorithm wants to exploit), they devote an enormous amount of effort to electromigration already. And the mismatch between that public understanding of the problem and the reality is causing a lot of warranty claims. You can see from enterprise fleets that CPUs don’t normally fail, yet every enthusiast knows someone who had a chip die “even without overclocking! I just enabled XMP!”. Of the failed CPUs getting returned for warranty, probably a plurality are memory overclocking failures. And this is only going to continue to get worse over time - 2.5D and 3D packaging are both progressively even more sensitive due to thermals, and have tighter requirements for voltage stability since they need to talk to the other dies at very low voltages (especially across heterogeneous dies with different metal stacks/totally different processes etc). https://semiengineering.com/3d-ic-reliability-degrades-with-increasing-temperature/ https://semiengineering.com/3d-ic-reliability-degrades-with-... https://semiengineering.com/on-chip-power-distribution-modeling-becomes-essential-below-7nm/ https://semiengineering.com/on-chip-power-distribution-model...

andrewstuart 3y ago

Expensive.

throw310822 3y ago

For those who just read the title: the "fuse" doesn't stop the cpu from working, it's just a flag for AMD support to know that the chip has been overclocked and this might invalidate the warranty.

actionfromafar 3y ago
To me this is actually a reasonable thing for AMD to do. It still leaves me free to do whatever I want with my property.
- machinekob 3y ago
  [flagged]
  - offices 3y ago
    If Nvidia/Apple/Intel used hardware fuses? Hahaha!
  - m_st 3y ago
    Apple has (had?) a water sensor in the iPhones to detect that the phone was in water. Didn't break anything, just signaled that there was water contact.
    - Zetobal 3y ago
      I tripped mine when I was in Vietnam... just because of the humidity.
  - weberer 3y ago
    I know Nvidia does the same thing in their Tegra chips. It stops you from downgrading to previous firmware versions on the Nintendo Switch.
  - jeffparsons 3y ago
    I kinda assumed that all the above companies would already be doing something similar. I want to live in a world with warranties, so if there's a non-privacy-violating way for companies to protect themselves a little bit from fraudulent warranty claims, why shouldn't they do it?

signa11 3y ago

apparently it does not void the warranty: https://www.tomshardware.com/pc-components/cpus/amd-says-overclocking-blows-hidden-fuses-on-ryzen-threadripper-7000-to-show-if-youve-overclocked-but-it-wont-automatically-void-your-cpus-warranty https://www.tomshardware.com/pc-components/cpus/amd-says-ove...

burrish 3y ago
It does not void the warranty, but the overclocking is permanent and any damage that happens when overclocked isn't managed by the warranty (if I read everything right)
Dalewyn 3y ago
AMD also says it will in one of their hidden footnotes at the bottom of a marketing page: >Overclocking and/or undervolting AMD processors and memory, including without limitation, altering clock frequencies / multipliers or memory timing / voltage, to operate outside of AMD’s published specifications will void any applicable AMD product warranty, even when enabled via AMD hardware and/or software. From: https://www.amd.com/en/technologies/expo https://www.amd.com/en/technologies/expo The moral of this story is overclocking is not for the naive nor the ignorant, and you must be willing to write off any hardware subjected to overclocking.
- Narann 3y ago
  Does it means that CoreCtrl can blow the fuse when underclocking? I’m doing this to avoid my CPU push the fans when doing casual browsing.

sylware 3y ago

Ofc it is not voiding the warranty, since I would be not surprise it would blow even if people sincerely did not engage in overclocking.

nicolaslem 3y ago
Similar e-fuses are common for preventing downgrading firmware, especially on consoles. Nintendo was famously running out of e-fuses to blow on the Switch because of the many vulnerabilities the console had. Point being that these e-fuses don't blow up randomly by themselves.
- sylware 3y ago
  Indeed, but trusting there is only one cause and it is always on user will is just abusive.
- 127361 3y ago
  That already happened on Xilinx Zynq FPGAs, where an incorrect power supply sequence causes random writes to one of the internal buses, which overwrites various eFuses, even after they have been locked. https://support.xilinx.com/s/question/0D52E00006hpKdKSAU/zynq-arm-core-1-bricked-due-to-efuse-bit-corruption?language=en_US https://support.xilinx.com/s/question/0D52E00006hpKdKSAU/zyn... I understand burning eFuses is necessary during production, but having them blowable when the device is operating normally could be compared to building disposable devices. One logic or software error and the device can be bricked permanently. That is a ridiculous state of affairs. What about single event upsets or some EMI induced glitch causing eFuse corruption? The power for burning the important fuses should be off at all times during normal operation. And we can have a test pad to supply the VPP during production. In the case of the AMD processors, a separate bank of fuses can be used to store diagnostic data for warranty returns, if necessary. If those get corrupted somehow, the device won't malfunction. But the important ones should not be possible to program after manufacturing, no matter what happens to the logical state of the hardware, period.

esskay 3y ago

I see no problem with this. If you overclock and damage you obviously shouldn't be able to claim warranty. The only thing that isn't as black and white is how they know if an overclocked faulty chip is faulty because of the overclock, or something else.

bob1029 3y ago

The use cases for overclocked CPUs are dead to me. There are so many other dominating factors that it is almost pointless to worry about per core frequency. Memory bandwidth is probably a bigger constraint for many practical applications. Faster core clocks doesn't do anything to resolve that.

burrish 3y ago

I mean... is it really necessary to overclock a AMD Threadripper, for the price of this new Threadripper ($9,999) I wouldn't take the risk of overclocking it..

account42 3y ago
> I mean... is it really necessary to overclock a AMD Threadripper Yes? The main point of the Threadripper (especially non-PRO) is that you have a many-core CPU that can still run at high frequencies. Othervise EPYC (many-core) or Ryzen (high speeds) would be enough.
- burrish 3y ago
  Ah I see thanks, but still for this generation of Threadripper, I would avoid overclocking it if it means having no warranty. Also shit move from AMD because even if you overclock with their software, the warranty still becomes void
unregistereddev 3y ago
It depends. If I'm an IT manager at Pixar and this is going in the workstation of my best and most productive animator, the price might not matter. If reducing the time s/he spends waiting on the computer means I can produce movies faster, I'll take risks to give them the best machine possible. If I'm a home freelancer staking my livelihood on this workstation, I'm not taking the risk.

account42 3y ago

Of all the CPUs I have had not a single one broke from use before they were replaced due to obsolescence and I definitely have been pushing them. How common is CPUs being permanently damaged from reasonable overclocking anyway, especially modern ones that have integrated sensors and clock themselves down automatically?

bravetraveler 3y ago
CPUs are still pretty durable but they can be a bit temperamental. With the smaller process sizes there's less voltage tolerance before degradation occurs. The X3D chips from AMD pack things supposedly pack the cache so tightly that it's easy to get into trouble A lot of chips burned out with something relatively mild like 1.3V on the SOC! That protection is fairly limited. There aren't enough sensors for everything that's heat sensitive. Reducing voltages/clock speeds also may not be enough to save all of those. Very long way to say: not that common... but decently. edit: As Paul mentions in a peer comment, this is largely due to the memory controller being moved onto the CPU.
paulmd 3y ago
anecdotally, probably at least 25% of enthusiasts have had a cpu that "randomly died" or "started getting unstable over time" even though they supposedly never overclocked it, and the leading cause there is memory controller degradation caused by XMP. I had a 9900K fail due to XMP, no other overclocking.

amelius 3y ago

Why don't they just put some thermal feedback system in it, making the chip inherently safe?

kayodelycaon 3y ago
Thermal throttling has been a thing for a long time.
- bravetraveler 3y ago
  Also only partially effective! A chip that's: * on * idling * at room temperature ... is slowly degrading. This is only expedited by raising voltages when overclocking. Current passing through conductors wears them down. More current or heat means faster. What's more, there aren't enough sensors (or room to put them) for every heat-sensitive component.

blagie 3y ago

Speaking as an engineer, this is an essential feature. From AMD's language, and common sense, the thoughts on this impacting warranty are misguided. I suspect this is a normal feature designed for debugging. If I am AMD, and I e.g. receive 20,000 defective / failed chips returned from a bad run, or am sampling failures to just improve reliability, I want to know how those devices failed. If, what's failing, are overclocked chips, I probably do want to lock down chips, void the warranty, or similar. If what's failing is a distribution of chips representing real-world use, I want to address the defect. In either case, if doing an RCA to understand the defect, I want to know how the chip was used. Reporting of maximum temperature, voltage, overclocking, etc. (all the data HDD keep in SMART) is super-helpful for that sort of analysis. Also: Voiding warranty for overclockers would have been dumb. I've never overclocked, but for anyone here running a business: Vocal thought leaders are important to your brand. Overclocking may be out-of-spec, but if you want the word on the street to be that your chips are awesome, they had darned well be singing your praises. I've never overclocked, but I've cost both Google and AMD millions of dollars of business: * I used to do business with Google before they broke my personal account, wiped out data for a startup I was working with, and broke / discontinued several services I rely on. I'm well enough known that me going around saying "Don't build a business on Google" (and ditto for many other folks on HN) means that GCP is starting a 100 meter dash with Azure and AWS about a hundred extra meters back. * I bought an AMD GPU for machine learning since I liked open-source. It didn't work, and AMD discontinued support a few months after I bought it. AMD wouldn't provide warranty support for lack of suitability to advertised purpose. I learned my lesson, and tools I'm building (which will likely have broad-based adoption) don't support AMD. There are customers you want to treat like a restaurant treats a food critic. It's not about them being profitable directly, but they're super-important.

ouraf 3y ago

That's similar to the e-fuses cellphone manufacturers use to know when a phone was rooted and void warranty regardless of what caused the malfunction, right?

127361 3y ago

I really don't like the idea of having field-programmable OTP memories in microprocessors. This shouldn't be possible, there should be a physical VPP pin (as in MediaTek SoCs), if you don't supply power to this then no fuses are blowable. Otherwise we're going to have ransomware physically brick CPUs if you do not pay up on time. There's even worse possibilities, I think some hardware has ~1KB of executable OTP which can be programmed in that manner - so it may just be possible to implement some kind of backdoor that resides in the physical CPU. Maybe something only a state-level attacker could do. For example, it could prevent CPU side-channel mitigations from ever working, somehow, e.g. by repeatedly writing to a private internal register to stealthily keep the CPU vulnerable. And few would ever know about it, because it's hidden in an on-chip security processor. Personally I utterly hate all AMD chips which have a Platform Security Processor. Locking down your own property to prevent you from accessing it should be illegal. There is a full Trustronic Trusted Execution Environment running in there, on both GPU and CPUs, I believe. For example the TEE firmware blob for a radeon GPU on Linux is "/lib/firmware/amdgpu/psp_13_0_7_sos.bin", with "sos" meaning Secure Operating System. And some of these firmware files are encrypted, so you can't reverse engineer them. The moment some ARM SoC company such as Rockchip comes up with a chip that's within an order of magnitude in performance, then my AMD chip (EPYC) is going in the bin. After being smashed to pieces with a hammer, live on YouTube, with an explaination why. That might get AMD marketing to pay attention. Update: Ampere Altra CPUs have seperate power pins for blowing eFuses, you can find it in the public datasheet here[1], on page 55, the supply pins are EFUSE_MFG_VDDQ1P8 and EFUSE_PCP_VDDQ1P8. It says tie to GND if unneeded. Also they have a public datasheet for the chip. I wonder if we can buy unfused CPUs without secure boot enabled? Or is that the default state of the chip? Could someone design a simple and cheap open-source motherboard for one of these processors, it's only a matter of time before the chips start turning up on Ebay? We will need more documentation from Ampere than just the datasheet, of course. 1. https://uawartifacts.blob.core.windows.net/upload-files/Altra_Max_Rev_A1_DS_v1_15_20230809_b7cdce449e_424d129849.pdf https://uawartifacts.blob.core.windows.net/upload-files/Altr...

CoastalCoder 3y ago
I'm guessing that vulnerabilities tied to ongoing manufacturer control (CPUs, cars, Polish locomotives, etc.) will continue until a widespread attack turns public opinion. And I fear that even then, lobbyists and/or intelligence agencies will neuter any response. Shoot, now I'm just making myself depressed.

giardini 3y ago

Opening of a sci-fi novel: Chinese manufacturers embed a Trojan horse mechanism into chips and batteries. The mechanism, triggered remotely by predetermined signal, disables chips and causes batteries to short-circuit and explode.