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AMD Zen Microarchitecture: Dual Schedulers, Micro-Op Cache and Memory Hierarchy

190 points by dineshp2 10y ago

tcoppi 10y ago
The timeframe is slightly disappointing since I think a lot of people were expecting Q3/Q4 2016. The architecture itself sounds pretty much like what everyone was expecting, a traditional fat and wide core. Their power management and foundry process will probably make the difference as to whether final performance is impressive or not, may also be the cause of the delay.
- BlackMonday 10y ago
  AMD stated for a while (march or so) that they maybe have small shipments in december, but the bulk of shipments will realy only start in Q1 2017. Anyway, the first benchmark is promising, and I hope Zen can also keep up with Broadwell performance in other benchmarks/workloads, as well as in power efficency.
snuxoll 10y ago
Not having a unified L3 cache is an interesting choice, I can see how it would significantly reduce the cost of the chip and considering many multi-threaded workloads are operating on separate chunks of data chances are it shouldn't incur a noticeable performance penalty (especially in virtualization workloads, I'm interested to see what their 32-core server chip ends up looking like).
- tcoppi 10y ago
  It could even help with low threadcount workloads since the L3 will presumably be able to be fewer cycles away from each core than a unified last level cache would be.
- gpderetta 10y ago
  On the other hand an unified (inclusive) L3 cache helps with maintaining cache coherency, which need to be explicitly handled in a non-unified design. I guess a big benefit of the separate caches is that if only half cores are in use, you can power half of it down, saving power and TDP.
  - tcoppi 10y ago
    Cache coherency might not necessarily be an issue if they treat each Cores->L3 pair as a NUMA node. I don't think they are doing that since we probably would have already heard about it if they are, but AMD has done crazier things before, and they are pretty good at NUMA architectures.
    - gpderetta 10y ago
      what do you mean? NUMA nodes are still coherent.
      - tcoppi 10y ago
        You're right, I don't know what I was thinking.
  - sliverstorm 10y ago
    A unified L3 is expensive in a number of ways. It is large, which means it is geographically remote, as well as slow (for caches, big == slow). This costs lots of access latency. It also has a bandwidth problem. If 64 threads are vying for access, you either build it with few access ports and it gets choked, or you build it with many access ports which is costly in area, power, & speed. Two separate peer caches automatically have twice the bandwidth of one similar double-size cache, for the price of NUMA & cache coherency challenges. There is no one right answer here. Bandwidth is far more important and coherency much easier in a small L1; as you go down the hierarchy, bandwidth needs shrink and coherency is more expensive.
    - BlackMonday 10y ago
      I remember a rumour about a HPC-APU from AMD which would combine 16 Zen cores with a Vega GPU and HBM (High Bandwith Memory) as a L4 cache. I know a L4 cache would be much slower than a L3 cache, but I'm curious, could HBM as a L4 cache be one of the reasons why they didn't use a unified L3 cache? Disclaimer: I don't know sh*t about hardware design as you can probably guess from my posting. ;o)
- deleted 10y ago
  [deleted]
arcanus 10y ago
I've been recently reading reports from some of my banking friends (and actually chatted with some folks I know at AMD) because I'm curious about AMD's turnaround. Even just last year AMD looked to be in very dire straights, and are still operating at a loss. However, they seem to have a strong technical pipeline and they have historically punched above their weight-class. Does it look like they are going to make it?
- koolba 10y ago
  AMD seems to operate like a middle America mom and pop sandwich shop. Products are decent, lots of people rooting for them to succeed, they never seem to pull ahead, yet they also manage to live on (if only to continue their struggle).
  - PedroBatista 10y ago
    Story of my life.
- tcoppi 10y ago
  I don't think they are in any danger of bankruptcy. Whether they return to profitability is still an open question but it seems likely that they should be by some point next year. How profitable, and what happens after that, is anyone's guess. There is a lot of room to grow in the graphics and CPU space, but they have tough competitors. I do think their stock is very fairly valued at ~$6 though, I think any potential gains from Zen over the next year or so are priced in to that. It definitely isn't a value buy anymore. Edit: As the day goes on it seems like they're trading back over $7, so obviously the market disagrees with me :) They were trading around $10 before losing profitability, and in the $20-$40 range during their mid-2000s heyday, so maybe the market is expecting performance closer to that. I think that is optimistic still, but again who knows.
  - blueprint 10y ago
    IMHO it's not actually possible for something to ever be 100% priced in, which has the surprising meaning that people need to also discuss how much of an event is priced in when they speculate whether something is or isn't priced in.
maerek 10y ago
As someone who is fascinated by articles like this one, but doesn't have a background in CE/EE, any recommendations for literature/classes I could take so that I can better understand the topics being discussed?
- tcoppi 10y ago
  A computer architecture class. For books, [1] is what you will probably use in any decent computer architecture class, and [2] is a good read from a more general audience perspective, if a bit dated. 1. https://www.amazon.com/Computer-Architecture-Fifth-Quantitative-Approach/dp/012383872X/ref=sr_1_1?ie=UTF8&qid=1471536721&sr=8-1&keywords=hennessy+and+patterson https://www.amazon.com/Computer-Architecture-Fifth-Quantitat... 2. https://www.amazon.com/Inside-Machine-Introduction-Microprocessors-Architecture/dp/1593276680/ref=sr_1_1?ie=UTF8&qid=1471536789&sr=8-1&keywords=inside+the+machine https://www.amazon.com/Inside-Machine-Introduction-Microproc...
  - deaddodo 10y ago
    I would argue that this is the best: https://www.amazon.com/dp/B00HCLUL5O/ref=dp-kindle-redirect?_encoding=UTF8&btkr=1 https://www.amazon.com/dp/B00HCLUL5O/ref=dp-kindle-redirect?... Albeit, slightly older and very technical.
- dr_zoidberg 10y ago
  Read this link: http://www.lighterra.com/papers/modernmicroprocessors/ http://www.lighterra.com/papers/modernmicroprocessors/ It's a good mix between high-level and highly-detailed.
- paulmd 10y ago
  I very much recommend Agner Fog's Microarchitecture. It's a rather ponderous tome, but it is quite simply the definitive resource on the actual design and performance of real-world x86 CPUs. It does have a brief introduction on some of the basic execution fundamentals but then it jumps right in, so you will probably need some external introduction if you are not generally familiar with the topic. http://www.agner.org/optimize/microarchitecture.pdf http://www.agner.org/optimize/microarchitecture.pdf
akerro 10y ago
Should I wait for Zen or buy i7 now?
- arca_vorago 10y ago
  I decided to wait for Zen months ago. I sure hope its worth it. My plan is zen beast for vr gamedev/play (on linux, not windows) Cant VR without the computer to support it, and 90fps keeps the VR discomfort away.
  - daveguy 10y ago
    Wait for Zen, but evaluate benchmarks. You can probably still get a cheaper Intel then even if amd doesn't live up to the hype (because at least amd will be closer).
- theandrewbailey 10y ago
  Depends on what you have and how urgently you need the greater speed. My main system is still running a i7-2600 from over 5 years ago. That GTX 680 I have in there is still plenty fast. The upgrade question is: how pretty do I want Star Citizen to be?
  - akerro 10y ago
    I would like to build a PC that would compile stuff quickly... Android, Java, Spring/Hibernate, some Rust and JS recently. Currently takes a few minutes to build any of my projects on a laptop I have. I think more physical cores will boost it more?
    - rkalla 10y ago
      Generally speaking... "productivity" and media styles of workloads do better with more cores/high memory machines. Gaming typically does better with higher clock speeds (which means less cores in every case I've seen). If you want that in a laptop form factor though, I am not aware of Intel sticking massive-cored chips in the mobile form factor, so your choices will be limited to whatever the fastest i7 is you can pickup... unless you were thinking of building a desktop? UPDATE - Oh mutagen's point about SSD is absolutely spot on... the faster the storage the better _first_... then worry about the rest of that stuff I mentioned.
geertj 10y ago
SEV (Secure Encrypted Virtualization, [1]) is a hugely interesting feature that will be available with Zen. Once it's mature and perfected, it would allow you to securely run a VM in the cloud that is protected against someone who controls the hypervisor. And you'd also be able to attest that indeed you're running in such a protected VM. How do you protect against someone controlling the hypervisor? Read the paper. But the high level is to encrypt memory using keys that cannot leave the processor and are only available to a specific VM ASID (Address Space Identifier), assisted by a secure firmware similar to the Secure Enclave. Attestation uses an on-chip certificate signed by an AMD master key during fabrication. There were some discussions on this on the linux-kernel mailing list [2]. As I understand it, the current generation of SEV is still somewhat leaky, but there's no fundamental reason why those leaks cannot be closed. [1] http://amd-dev.wpengine.netdna-cdn.com/wordpress/media/2013/12/AMD_Memory_Encryption_Whitepaper_v7-Public.pdf http://amd-dev.wpengine.netdna-cdn.com/wordpress/media/2013/... [2] http://www.mail-archive.com/linux-doc@vger.kernel.org/msg02578.html http://www.mail-archive.com/linux-doc@vger.kernel.org/msg025...
- tcoppi 10y ago
  This is interesting. The most compelling use case IMO is protection against cold boot attacks rather than virtualization, at least until SEV has been proven empirically to do what they claim. Virtualization security is hard to get right in general and adding another layer of complexity probably won't help in the short term.
  - emn13 10y ago
    Even if it turns out to be leaky, it could still be a big deal: I think it's fair to say that the greatest cloud risk isn't actively and persistently hostile providers - mostly because that sounds like an almost hopeless task. A more realistic risk is that via a VM-breakout or other hack hostile code manages to run on the hypervisor or to at least indirectly influence the hypervisor and other VMs. And that kind of code may well be harder to exploit with even slightly leaky encryption. A hacked hypervisor may not be entirely under the control of the hacker; or breaking the encryption may cause side-effects (such as instability) that causes watchers to take note; or it may simply be quite complex and require case-by-case exploits that are generally impractical. Even a less that perfect protection from the hyper-visor may still have some value. I'd be more worried about the performance overhead, personally - I can't imagine using this if the impact is significant, and it seems like it almost has to be.
deleted 10y ago
[deleted]
mark-r 10y ago
I've been a big booster of AMD for a long time, but recently the performance/power is so much in Intel's favor that I've been forced to use Intel for my last couple of PCs. I hope Zen makes them competitive again.
Zardoz84 10y ago
The most important thing for me. Zen cores have the AMD equivalent of Intel AMT ? (I don't remember the name). If it haves it, I would avoid it like a pest, and get an FX-8370 or 8350 to replace my now aging FX-4100. The last thing that I like to have on my computer is a hidden uncontrollable CPU doing things that could affect to my privacy.
- SXX 10y ago
  What you talking about is Platform Security Processor (PSP) and according to libreboot website it's built in all their CPUs released since 2013.
  - snuxoll 10y ago
    Libreboot is inaccurate on this one, as far as I can tell this is only on the Puma chips right now, but it's likely it will make it's way to other chips as they come out. Newer Bulldozer-derived (Family 15h) cores made today such as the current FX lineup do not have the PSP.
    - Zardoz84 10y ago
      So, I'm going to grab an FX8350
      - dmm 10y ago
        Get the 8320e at Microcenter for $90 and over clock it. It'll be faster and cheaper.
- snuxoll 10y ago
  AMD has the Platform Security Processor in the Puma chips (Mullins and Beema) which serves the same purpose as the Intel ME (Management Engine). I would not be surprised if this made its way into Zen.
- milcron 10y ago
  Unfortunately, it seems impossible to acquire a modern x86/x64 chip without such hidden firmware. The last Intel CPUs without it are from 2008, and the last AMD CPUs without it are from 2013. If you can tolerate using a different CPU architecture, Raptor Engineering's Talos Secure Workstation looks very intriguing. https://www.raptorengineering.com/TALOS/prerelease.php https://www.raptorengineering.com/TALOS/prerelease.php
bitL 10y ago
Am I the only person whom the Zen logo makes cringe? They shouldn't copycat Intel Inside logo there. Really bad taste...
- evanriley 10y ago
  It's not copying the Intel Inside log, although I'll agree they look _similar_ its most likely based off of the Ensō[0], which is part of _Zen_ Buddhism. [0] https://en.wikipedia.org/wiki/Ens%C5%8D https://en.wikipedia.org/wiki/Ens%C5%8D
bitL 10y ago
I just wish AMD made drivers for Win 7 as well - then I could switch from 4-core 4790k/32GB to 8-core ZEN/64GB ECC and keep using all the Adobe video editing stuff.
- clevernickname 10y ago
  Citation needed. There would have been a huge stink if AMD had stopped supporting Windows 7 already.
  - bitL 10y ago
    http://techreport.com/news/29611/win10-will-be-the-only-windows-supported-on-next-gen-hardware http://techreport.com/news/29611/win10-will-be-the-only-wind...
    - gruez 10y ago
      The article states that it only applies to new CPUs/APUs. I also vaguely remember that Intel's doing the same as well
      - bitL 10y ago
        > only applies to new CPUs/APUs i.e. Zen
    - clevernickname 10y ago
      What is the practical implication of this? In China Windows XP on modern hardware is still by far the dominant OS, so I would be very surprised if any of the major manufacturers would stop releasing drivers for that, let alone 7.

190 points by dineshp2 10y ago

The timeframe is slightly disappointing since I think a lot of people were expecting Q3/Q4 2016. The architecture itself sounds pretty much like what everyone was expecting, a traditional fat and wide core. Their power management and foundry process will probably make the difference as to whether final performance is impressive or not, may also be the cause of the delay.

BlackMonday 10y ago
AMD stated for a while (march or so) that they maybe have small shipments in december, but the bulk of shipments will realy only start in Q1 2017. Anyway, the first benchmark is promising, and I hope Zen can also keep up with Broadwell performance in other benchmarks/workloads, as well as in power efficency.

snuxoll 10y ago

Not having a unified L3 cache is an interesting choice, I can see how it would significantly reduce the cost of the chip and considering many multi-threaded workloads are operating on separate chunks of data chances are it shouldn't incur a noticeable performance penalty (especially in virtualization workloads, I'm interested to see what their 32-core server chip ends up looking like).

tcoppi 10y ago
It could even help with low threadcount workloads since the L3 will presumably be able to be fewer cycles away from each core than a unified last level cache would be.
gpderetta 10y ago
On the other hand an unified (inclusive) L3 cache helps with maintaining cache coherency, which need to be explicitly handled in a non-unified design. I guess a big benefit of the separate caches is that if only half cores are in use, you can power half of it down, saving power and TDP.
- tcoppi 10y ago
  Cache coherency might not necessarily be an issue if they treat each Cores->L3 pair as a NUMA node. I don't think they are doing that since we probably would have already heard about it if they are, but AMD has done crazier things before, and they are pretty good at NUMA architectures.
  - gpderetta 10y ago
    what do you mean? NUMA nodes are still coherent.
    - tcoppi 10y ago
      You're right, I don't know what I was thinking.
- sliverstorm 10y ago
  A unified L3 is expensive in a number of ways. It is large, which means it is geographically remote, as well as slow (for caches, big == slow). This costs lots of access latency. It also has a bandwidth problem. If 64 threads are vying for access, you either build it with few access ports and it gets choked, or you build it with many access ports which is costly in area, power, & speed. Two separate peer caches automatically have twice the bandwidth of one similar double-size cache, for the price of NUMA & cache coherency challenges. There is no one right answer here. Bandwidth is far more important and coherency much easier in a small L1; as you go down the hierarchy, bandwidth needs shrink and coherency is more expensive.
  - BlackMonday 10y ago
    I remember a rumour about a HPC-APU from AMD which would combine 16 Zen cores with a Vega GPU and HBM (High Bandwith Memory) as a L4 cache. I know a L4 cache would be much slower than a L3 cache, but I'm curious, could HBM as a L4 cache be one of the reasons why they didn't use a unified L3 cache? Disclaimer: I don't know sh*t about hardware design as you can probably guess from my posting. ;o)
deleted 10y ago
[deleted]

arcanus 10y ago

I've been recently reading reports from some of my banking friends (and actually chatted with some folks I know at AMD) because I'm curious about AMD's turnaround. Even just last year AMD looked to be in very dire straights, and are still operating at a loss. However, they seem to have a strong technical pipeline and they have historically punched above their weight-class. Does it look like they are going to make it?

koolba 10y ago
AMD seems to operate like a middle America mom and pop sandwich shop. Products are decent, lots of people rooting for them to succeed, they never seem to pull ahead, yet they also manage to live on (if only to continue their struggle).
- PedroBatista 10y ago
  Story of my life.
tcoppi 10y ago
I don't think they are in any danger of bankruptcy. Whether they return to profitability is still an open question but it seems likely that they should be by some point next year. How profitable, and what happens after that, is anyone's guess. There is a lot of room to grow in the graphics and CPU space, but they have tough competitors. I do think their stock is very fairly valued at ~$6 though, I think any potential gains from Zen over the next year or so are priced in to that. It definitely isn't a value buy anymore. Edit: As the day goes on it seems like they're trading back over $7, so obviously the market disagrees with me :) They were trading around $10 before losing profitability, and in the $20-$40 range during their mid-2000s heyday, so maybe the market is expecting performance closer to that. I think that is optimistic still, but again who knows.
- blueprint 10y ago
  IMHO it's not actually possible for something to ever be 100% priced in, which has the surprising meaning that people need to also discuss how much of an event is priced in when they speculate whether something is or isn't priced in.

maerek 10y ago

As someone who is fascinated by articles like this one, but doesn't have a background in CE/EE, any recommendations for literature/classes I could take so that I can better understand the topics being discussed?

tcoppi 10y ago
A computer architecture class. For books, [1] is what you will probably use in any decent computer architecture class, and [2] is a good read from a more general audience perspective, if a bit dated. 1. https://www.amazon.com/Computer-Architecture-Fifth-Quantitative-Approach/dp/012383872X/ref=sr_1_1?ie=UTF8&qid=1471536721&sr=8-1&keywords=hennessy+and+patterson https://www.amazon.com/Computer-Architecture-Fifth-Quantitat... 2. https://www.amazon.com/Inside-Machine-Introduction-Microprocessors-Architecture/dp/1593276680/ref=sr_1_1?ie=UTF8&qid=1471536789&sr=8-1&keywords=inside+the+machine https://www.amazon.com/Inside-Machine-Introduction-Microproc...
- deaddodo 10y ago
  I would argue that this is the best: https://www.amazon.com/dp/B00HCLUL5O/ref=dp-kindle-redirect?_encoding=UTF8&btkr=1 https://www.amazon.com/dp/B00HCLUL5O/ref=dp-kindle-redirect?... Albeit, slightly older and very technical.
dr_zoidberg 10y ago
Read this link: http://www.lighterra.com/papers/modernmicroprocessors/ http://www.lighterra.com/papers/modernmicroprocessors/ It's a good mix between high-level and highly-detailed.
paulmd 10y ago
I very much recommend Agner Fog's Microarchitecture. It's a rather ponderous tome, but it is quite simply the definitive resource on the actual design and performance of real-world x86 CPUs. It does have a brief introduction on some of the basic execution fundamentals but then it jumps right in, so you will probably need some external introduction if you are not generally familiar with the topic. http://www.agner.org/optimize/microarchitecture.pdf http://www.agner.org/optimize/microarchitecture.pdf

akerro 10y ago

Should I wait for Zen or buy i7 now?

arca_vorago 10y ago
I decided to wait for Zen months ago. I sure hope its worth it. My plan is zen beast for vr gamedev/play (on linux, not windows) Cant VR without the computer to support it, and 90fps keeps the VR discomfort away.
- daveguy 10y ago
  Wait for Zen, but evaluate benchmarks. You can probably still get a cheaper Intel then even if amd doesn't live up to the hype (because at least amd will be closer).
theandrewbailey 10y ago
Depends on what you have and how urgently you need the greater speed. My main system is still running a i7-2600 from over 5 years ago. That GTX 680 I have in there is still plenty fast. The upgrade question is: how pretty do I want Star Citizen to be?
- akerro 10y ago
  I would like to build a PC that would compile stuff quickly... Android, Java, Spring/Hibernate, some Rust and JS recently. Currently takes a few minutes to build any of my projects on a laptop I have. I think more physical cores will boost it more?
  - rkalla 10y ago
    Generally speaking... "productivity" and media styles of workloads do better with more cores/high memory machines. Gaming typically does better with higher clock speeds (which means less cores in every case I've seen). If you want that in a laptop form factor though, I am not aware of Intel sticking massive-cored chips in the mobile form factor, so your choices will be limited to whatever the fastest i7 is you can pickup... unless you were thinking of building a desktop? UPDATE - Oh mutagen's point about SSD is absolutely spot on... the faster the storage the better _first_... then worry about the rest of that stuff I mentioned.

geertj 10y ago

SEV (Secure Encrypted Virtualization, [1]) is a hugely interesting feature that will be available with Zen. Once it's mature and perfected, it would allow you to securely run a VM in the cloud that is protected against someone who controls the hypervisor. And you'd also be able to attest that indeed you're running in such a protected VM. How do you protect against someone controlling the hypervisor? Read the paper. But the high level is to encrypt memory using keys that cannot leave the processor and are only available to a specific VM ASID (Address Space Identifier), assisted by a secure firmware similar to the Secure Enclave. Attestation uses an on-chip certificate signed by an AMD master key during fabrication. There were some discussions on this on the linux-kernel mailing list [2]. As I understand it, the current generation of SEV is still somewhat leaky, but there's no fundamental reason why those leaks cannot be closed. [1] http://amd-dev.wpengine.netdna-cdn.com/wordpress/media/2013/12/AMD_Memory_Encryption_Whitepaper_v7-Public.pdf http://amd-dev.wpengine.netdna-cdn.com/wordpress/media/2013/... [2] http://www.mail-archive.com/linux-doc@vger.kernel.org/msg02578.html http://www.mail-archive.com/linux-doc@vger.kernel.org/msg025...

tcoppi 10y ago
This is interesting. The most compelling use case IMO is protection against cold boot attacks rather than virtualization, at least until SEV has been proven empirically to do what they claim. Virtualization security is hard to get right in general and adding another layer of complexity probably won't help in the short term.
- emn13 10y ago
  Even if it turns out to be leaky, it could still be a big deal: I think it's fair to say that the greatest cloud risk isn't actively and persistently hostile providers - mostly because that sounds like an almost hopeless task. A more realistic risk is that via a VM-breakout or other hack hostile code manages to run on the hypervisor or to at least indirectly influence the hypervisor and other VMs. And that kind of code may well be harder to exploit with even slightly leaky encryption. A hacked hypervisor may not be entirely under the control of the hacker; or breaking the encryption may cause side-effects (such as instability) that causes watchers to take note; or it may simply be quite complex and require case-by-case exploits that are generally impractical. Even a less that perfect protection from the hyper-visor may still have some value. I'd be more worried about the performance overhead, personally - I can't imagine using this if the impact is significant, and it seems like it almost has to be.

deleted 10y ago

[deleted]

mark-r 10y ago

I've been a big booster of AMD for a long time, but recently the performance/power is so much in Intel's favor that I've been forced to use Intel for my last couple of PCs. I hope Zen makes them competitive again.

Zardoz84 10y ago

The most important thing for me. Zen cores have the AMD equivalent of Intel AMT ? (I don't remember the name). If it haves it, I would avoid it like a pest, and get an FX-8370 or 8350 to replace my now aging FX-4100. The last thing that I like to have on my computer is a hidden uncontrollable CPU doing things that could affect to my privacy.

SXX 10y ago
What you talking about is Platform Security Processor (PSP) and according to libreboot website it's built in all their CPUs released since 2013.
- snuxoll 10y ago
  Libreboot is inaccurate on this one, as far as I can tell this is only on the Puma chips right now, but it's likely it will make it's way to other chips as they come out. Newer Bulldozer-derived (Family 15h) cores made today such as the current FX lineup do not have the PSP.
  - Zardoz84 10y ago
    So, I'm going to grab an FX8350
    - dmm 10y ago
      Get the 8320e at Microcenter for $90 and over clock it. It'll be faster and cheaper.
snuxoll 10y ago
AMD has the Platform Security Processor in the Puma chips (Mullins and Beema) which serves the same purpose as the Intel ME (Management Engine). I would not be surprised if this made its way into Zen.
milcron 10y ago
Unfortunately, it seems impossible to acquire a modern x86/x64 chip without such hidden firmware. The last Intel CPUs without it are from 2008, and the last AMD CPUs without it are from 2013. If you can tolerate using a different CPU architecture, Raptor Engineering's Talos Secure Workstation looks very intriguing. https://www.raptorengineering.com/TALOS/prerelease.php https://www.raptorengineering.com/TALOS/prerelease.php

bitL 10y ago

Am I the only person whom the Zen logo makes cringe? They shouldn't copycat Intel Inside logo there. Really bad taste...

evanriley 10y ago
It's not copying the Intel Inside log, although I'll agree they look _similar_ its most likely based off of the Ensō[0], which is part of _Zen_ Buddhism. [0] https://en.wikipedia.org/wiki/Ens%C5%8D https://en.wikipedia.org/wiki/Ens%C5%8D

bitL 10y ago

I just wish AMD made drivers for Win 7 as well - then I could switch from 4-core 4790k/32GB to 8-core ZEN/64GB ECC and keep using all the Adobe video editing stuff.

clevernickname 10y ago
Citation needed. There would have been a huge stink if AMD had stopped supporting Windows 7 already.
- bitL 10y ago
  http://techreport.com/news/29611/win10-will-be-the-only-windows-supported-on-next-gen-hardware http://techreport.com/news/29611/win10-will-be-the-only-wind...
  - gruez 10y ago
    The article states that it only applies to new CPUs/APUs. I also vaguely remember that Intel's doing the same as well
    - bitL 10y ago
      > only applies to new CPUs/APUs i.e. Zen
  - clevernickname 10y ago
    What is the practical implication of this? In China Windows XP on modern hardware is still by far the dominant OS, so I would be very surprised if any of the major manufacturers would stop releasing drivers for that, let alone 7.