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Intel Core i “Haswell” CPUs May Require New Power Supply Units for PCs
- msandford 13y agoIt's surprising that these kinds of hiccups happen as infrequently as they do.
- ivybridge 13y agoHmmm. Maybe if they change the socket interface the new mobos can deal with this issue.
- lmm 13y agoThey'd have to change the ATX power socket on the motherboard, not the CPU socket; not impossible but it would be a shame after it's stood for this long.
- twoodfin 13y agoOnly if you want the C6/C7 states, which are the really low power draw ones. If you're the kind of person who builds your own PC, it's unlikely you really care about saving a few watts while in sleep. At worst, you'll get Ivy Bridge-level power consumption.
- dman 13y agoOn the contrary in 2013 the kind of person who builds their own PC's is the only one who likely cares about technical specs. If "good enough" is good enough for you there is very little reason to build your own box these days.
- freehunter 13y agoFor performance applications on the desktop though, power draw at idle doesn't matter too much. It's all about power draw at load. Power from the wall is cheap and easy to forget about. If I'm building a machine that draws 750W at load, drawing at idle is fairly insignificant. It's laptops where power draw at idle really matters, which are rarely home-built.
- criley 13y agoOn the contrary to your contrary: the kind of person who builds their PC is the kind who customizes how it works when they're using it. There's no automatic assumption that they also harbor green feelings and want lower power consumption for idle/sleep. Hell, many are proud of their beefy 1kW+ power supplies and the ridiculous power load they draw. Others are proud of their energy-destroying bit-coin mining setups. You certainly can't assume that the home builder cares at all about power consumption.
- dman 13y agoFair enough. On the other hand segments of the market who think of the computer as a blackbox that is a bicycle for the mind are even less likely to care about any individual specification. Most people I know who build their own PC's are trying to optimize for some spec that manufacturers dont usually care about - loudness, gpu performance, low power draw, size, aesthetics.
- jkldotio 13y ago>Others are proud of their energy-destroying bit-coin mining setups. I'd be proud of my bitcoin mining setup too if it could violate the laws of thermodynamics.
- jlarocco 13y agoOn the other hand, you can't automatically assume they don't care about it at all. I build most of my desktops, and I certainly want to reduce power usage when I'm not using them. Enough so that I'd pay for a power supply that supports the lower power states. Not everybody who builds their own PC is doing so to make a ridiculously over powered system.
- hga 13y agoHow about the MTBF spec? I exclusively use server or workstation/server class motherboards from Supermicro or Tyan not just for myself but also for my parents, so I can then largely ignore the hardware for 5+ years plus not worry about non-reproducible errors from radiation flipping a DRAM bit. I've done this since 1995-6 and never had one fail in the field except through an act of God (http://en.wikipedia.org/wiki/2011_Joplin_tornado http://en.wikipedia.org/wiki/2011_Joplin_tornado). For this purpose, decreasing stress from thermal cycling is good. (Yeah, they're grossly overpowered for what my parents do, but since I'm not including my labor in the cost they really don't cost that much.)
- EvilLook 13y agoI consider it borderline negligent to use anything other than ECC RAM in any machine where you care about not corrupting your data with a flipped DRAM bit.
- ars 13y agoExcept it's virtually impossible to find a CPU that supports ECC. I've used ECC in every one of my machines for the last decade or so - except for the very last once since it's was impossible to get without spending a crazy amount of money (xeon processor).
- tolle 13y agoMost AMD processors support it. At least the AM3/AM3+ ones. But only ASUS seems to have support for it enabled on the motherboards.
- EvilLook 13y agoIt's not virtually impossible. It may be virtually impossible in crappy cheap boards from Taiwan, but if you're buying cheap parts then you're likely not making money off the results that you're producing.
- ars 13y ago
- coldtea 13y ago>As it appears, end-users will either have disable low-power states of Haswell or get a new power-supply units compatible with the new Intel chip. Low power consumption is not one of the specs the PC building crowd really cares about. Especially if it means taking a performance hit.
- wmf 13y agoExcept in the case of HTPCs.
- gshubert17 13y agoThe difference between a 0.5 amp minimum current on the 12 volt supply and the 0.05 amp minimum current on the CPU might be enough to power a CPU fan (such as the Precision 690 from Dell, which is about 0.45 amp at 12V). I'm not familiar with other hardware requirements or constraints, so it might not work.
- kwantam 13y agoPerhaps someone will helpfully design a "PSU stability dongle" comprising a 26.1 Ohm resistor (standard 1% resistor value sufficient to ensure >450mA from 12V) and a Molex connector. Make it a passthrough. Of course, it'll have to be a >5W resistor, but that's what I like to call an opportunity to excel: just more room to add some rakish heat sink fins. You could even spend some of your power wasting budget on LEDs instead, but obviously we'll have to charge more for that model. The margins, you see.
- MertsA 13y agoTechnically it would have to be on the same rail as the 12V CPU power connector so a Molex 8981 connector (http://en.wikipedia.org/wiki/Molex_connector#Disk_drive_connector_.28Molex_8981_Series_Power_Connector.29 http://en.wikipedia.org/wiki/Molex_connector#Disk_drive_conn...) wouldn't cut it.
- joenathan 13y agoMolex is a company that makes many different types of connectors, so a Molex connector would cut it. http://www.molex.com/molex/search/keyword_select.jsp?channel=Products&chanName=Product%20Name http://www.molex.com/molex/search/keyword_select.jsp?channel...
- blappu 13y agoCouldn't Haswell motherboards automatically test the PSU on bootup?
- gvb 13y agoNot likely. The problem is that the PSU will shut down (self protection) if it has less that its minimum current draw. It has to do this because the voltage regulation loop goes unstable if it was designed to have a higher minimum current draw. If the PSU didn't shut down, it would fry things, including itself. Really bad. To test the PSU works at 0.5A would end up shutting down the computer if the PSU didn't work at 0.05A... exactly what happens today. Unfortunately, at that point it is too late to tell the user "your PSU is old" or to quickly connect a resistor across the +12v rails to work around the problem. As an experiment, find an old PSU and plug it into the wall (nothing connected to the power output connectors). It won't power on. If you connect a 2 ohm 10W resistor (or two 1 ohm 5W resistors in series) into the "hard drive" Molex connector +12v (yellow) to ground (black), it should start up and be happy. Disclaimers: 1) The resistor will become quite warm quite quickly (6W), watch your fingers. 2) If you damage something, it is a learning experience, not my fault.
- cnvogel 13y agoNote: First and foremost it will not power up because the power-on pin (#14, most often green cable) is not connected to ground (any black cable). https://www.google.de/search?q=atx+power+supply+pinout&client=chrome-mobile&tbm=isch&tbo=u&source=univ&sa=X&ei=yFqBUYe4M8ml4ASog4DwDw&ved=0CDQQsAQ&biw=320&bih=460#i=6 https://www.google.de/search?q=atx+power+supply+pinout&c... The most likely outcome though is that the supply will just power on and idle without any load. Rapid transients on the rails (say from 100W to ~0W) might cause the over voltage crowbar to trip, though.
- CamperBob2 13y agoAh, yes, the other side of the Halting Problem: not only can you not tell if your program will ever halt, but you also can't tell if your program has been externally halted.
- astrodust 13y agoI'm still perplexed why Intel doesn't redesign their CPU socket to be more efficient at delivering power. They're channelling a lot of juice through some very tiny pins or pads, a fairly straight-up evolution of the old 8088 chip that fit into a DIP socket. Is it somehow not practical to have several bigger pins for power that can handle more current than to have literally hundreds of pins dedicated to power? A surprising percentage of the pins on a modern Intel chip do nothing more than power the chip. The traditional pair of +Vcc and GND pins just can't cut it, apparently, and no wonder with some chips drawing over 100W of power. Not too long ago video cards started taking a direct feed from the PSU rather than relying on the PCI or PCIe bus. It's surprising the same thing hasn't happened to high-power integrated circuits.
- akiselev 13y agoThe vast majority of power efficiency losses are in the copper interconnects within the chip, not the copper pins. Oh also, if you want fewer power pins, get ready for more heat and way more expensive CPUs. The pins are placed to be as cost effective and efficient as possible to power the individual chip modules (many of which will operate at different voltages). Also, it's way cheaper to convert power on the motherboard than within an already incredibly constrained CPU package. Edit: "vast majority" as far as power and other connections to the board go, the transistors create way more heat than the interconnects.
- nilsimsa 13y agoChips have multiple power pins for signal integrity issues. You want the power source close to where it is being used, particularly for IO pads. Even chips with low power requirements will have multiple power pins.
- stephengillie 13y agoIt's sorta like plugging your PC into the wall plug next to it, and plugging your toaster into the wall plug in your kitchen...Yea, it would be easier to daisy-chain surge protectors from 1 outlet, but that's so messy. Like interior design layout, like circuit design layout? And (I think) the copper circuits are so close that quantum leaps can occur -- electrons can just decide to jump from one piece of copper to another, straight through silicon or anything else, simply because the copper is so close. This means a VCC line can be giving charge to an unpowered neighboring circuit or memory cell without magnetically affecting it.
- petermonsson 13y agoI'm going to make a wild guess that the C6/C7 states are intended to be used in notebooks and other battery powered devices. For desktops the rest of the system will easily loose 5W somewhere else.
- wtallis 13y agoJust how much of the system is getting shut off in these new C-states? A lot of the best power supplies have a single 12V rail, and the 3.3V and 5V rails are provided by stepping down the voltage from the 12V rail. It seems like any PSU with that kind of design wouldn't be affected unless the total system power consumption drops below 6W, which would require shutting off at least the expansion cards, disk drives, any power-hungry USB devices, and potentially the case fans. Even 4 DIMMs plus the keyboard and mouse necessary to wake up the system might be sufficient to keep the power draw high enough.
- ajross 13y agoFTA, quoting Robert Pearce: "I fully expect the [motherboard] companies to disable C6/C7 in the BIOS (though consumers could enable it if they chose to) as there are simply too many PSU's in the market space which might not work correctly." ... because the motherboard manufacturers can't figure out how to stuff a 240 ohm resistor across the 12v rail? Edit to be fair: if the power savings from going from the legacy suspend to the Haswell states is less than 600mW, then this isn't worth it and disabling the Haswell states is the right solution. In my experience though, PC motherboards almost never idle at less than 3-5W.
- stephengillie 13y agoIt's like how motherboard manufacturers couldn't figure out how to keep the voltage regulators on their boards from overheating in the summer and desoldering themselves.
- venomsnake 13y agoAfter how many years of standby will the savings of the low power state justify replacement on a 200$ PSU that is 80+ platinium rated? And anyway power states must be disabled for decent overclock to be achieved.
- coldtea 13y ago>As it appears, end-users will either have disable low-power states of Haswell or get a new power-supply units compatible with the new Intel chip. Errr, is not like many end users update their desktop PC with new CPUs anyway. And those very few that do, they also buy a new motherboard, so to get a new power supply is nothing significant in comparison.
- MikeKusold 13y agoEveryone will need to buy a new Haswell motherboard. Unless the reports I've read months ago changed, Haswell is going to be on a new socket.
- nivloc 13y agoCorrect. Haswell is LGA 1150, SB/IB were LGA 1155.
- batgaijin 13y agoWTF is up with this? Is Intel just taking as much money as they can? Or are these legitimate issues that they waited to address?
- wtallis 13y agoThere weren't any legitimate technical reasons for switching from LGA1156 to LGA1155, but Haswell and LGA1150 are introducing major changes to power delivery and voltage regulation. Given that power delivery accounts for something like half the pin count of a modern CPU, a new socket for Haswell is quite justified. (Although, those power delivery changes only really benefit the mobile market, but Intel's long been unwilling to produce different dies for the desktop market and the mainstream mobile market.)