News AMD: Windows 11 Slows CPUs Up To 15%, Patch Coming

wifiburger

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Windows 10 build 21H1 which very close to Windows 11 build 21H2 also has CPPC broken on my Zen2 3900x.

Fresh install, AMD Chipset driver, updates done and the CPPC ranking of the cores are ignored. Very poor ST boost & most threads are sent to weak cores(2nd CCD).

setting CPPC off in the bios fixes this but adds some memory latency so I set it back on and turned off CPPC boosting in Windows.

Powercfg -setacvalueindex scheme_current sub_processor PERFBOOSTMODE 2
Powercfg -setactive scheme_current

Are we also getting 21H1 update to resolved this CPPC bug ?

AMD also advises that its customers experiencing the issues can "continue to use a supported version of Windows 10,"

well.... as long as it's not the latest Windows 10 21H1, they share the same kernel/ crap scheduling
 
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Makaveli

Splendid
Windows 10 build 21H1 which very close to Windows 11 build 21H2 also has CPPC broken on my Zen2 3900x.

Fresh install, AMD Chipset driver, updates done and the CPPC ranking of the cores are ignored. Very poor ST boost & most threads are sent to weak cores(2nd CCD).

setting CPPC off in the bios fixes this but adds some memory latency so I set it back on and turned off CPPC boosting in Windows.

Powercfg -setacvalueindex scheme_current sub_processor PERFBOOSTMODE 2
Powercfg -setactive scheme_current

Are we also getting 21H1 update to resolved this CPPC bug ?

AMD also advises that its customers experiencing the issues can "continue to use a supported version of Windows 10,"

well.... as long as it's not the latest Windows 10 21H1, they share the same kernel/ crap scheduling

I'm not seeing this on my Zen 3 cpu but i'm only on 8 core so single CCD.
 
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ezst036

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Didn't Pat Gelsinger brag about AMD's lead being over and Intel taking the lead?
Sure, when the OS is setting AMD CPUs back by 15% and improving on Intel CPU performance... who wouldn't take the lead?

This is a very interesting observation that is likely a little less nefarious. I would suspect that the new Windows is first and foremost programmed for Intel's Thread Director in the scheduling department. To word this generically, Windows 11 is less capable now of using a traditional multi core processor and needs the core moderation capability of a thread directing feature for full throughput.

Conversely, what this means is that when AMD implements its own big.LITTLE by integrating its bobcat/beema cores with (Zen 5?), they get a free 15% boost. They'll have to have a Thread Director as well that Windows can talk to.

https://www.tomshardware.com/reviews/amd-tablet-processor,3813.html
 
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kaalus

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They don't need to speed up Win 11. Much easier to slow down Win 10 in the next update. Oh, the joys of monopoly!
The only solution is to split up Microsoft, Apple, Facebook, Amazon, and all other companies, including those from cosmetics, energy, health sectors, having a disproportionate share in any market.
 

LeviTech

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Are AMD 3015e and AMD 3020e affect by this bug?
Other question is, can this bug damage the CPU's?
 
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btmedic04

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This is a very interesting observation that is likely a little less nefarious. I would suspect that the new Windows is first and foremost programmed for Intel's Thread Director in the scheduling department. To word this generically, Windows 11 is less capable now of using a traditional multi core processor and needs the core moderation capability of a thread directing feature for full throughput.

Conversely, what this means is that when AMD implements its own big.LITTLE by integrating its bobcat/beema cores with (Zen 5?), they get a free 15% boost. They'll have to have a Thread Director as well that Windows can talk to.

https://www.tomshardware.com/reviews/amd-tablet-processor,3813.html

it would be interesting to see if there is a respective up to 15% reduction in performance for rocket lake. that would confirm your theory in my eyes. However until that is tested, I remain suspicious
 
Im pretty sure this is just a mess up from Microsoft.. isn't it?

Or maybe AMDs fault, not providing enough info since 2017 when Ryzen launched..... right?....

If it starts like this Im guessing next months will be fun.
 

kep55

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Why should AMD have to do ANYTHING? It's microsoft's fault their cpu sux for air. I've said since win11 (and win10) was introduced that microsoft's hardware requirememnts have nothing to with function. It has everything to do with placating all the software and hardware sycophants and boot-lickers and loading their coffers.
 
Oct 5, 2021
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AMD: Windows management team finally woke up and sketchy stuff were doing is suddenly hampered.

I've been an AMD user since the early 2000's (unlocking your packages with a graphite pencil). Enough is enough already..

Time for some more ethical business practices, Lisa. Stop taking intellectual property which isn't yours for granted..
 
Oct 5, 2021
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Im pretty sure this is just a mess up from Microsoft.. isn't it?

Or maybe AMDs fault, not providing enough info since 2017 when Ryzen launched..... right?....

If it starts like this Im guessing next months will be fun.
Yup AMD's fault for not sending software engineers to look over the shoulders of Microsoft and Intel when they were designing win11 for AlderLake. 😁
 
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Oct 5, 2021
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Yup AMD's fault for not sending software engineers to look over the shoulders of Microsoft and Intel when they were designing win11 for AlderLake. 😁

Better every read loop! cheers..
 

excalibur1814

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Microsoft creates an operating system. Cool. It's up to AMD to test that operating system and to then provide suitable drivers. AMD have had a LONG time to get things ready.

They haven't. Oh well.
 

kwohlt

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Why should AMD have to do ANYTHING? It's microsoft's fault their cpu sux for air. I've said since win11 (and win10) was introduced that microsoft's hardware requirememnts have nothing to with function. It has everything to do with placating all the software and hardware sycophants and boot-lickers and loading their coffers.

What do you mean? AMD's responsible for their own drivers, and there was enough lead time to get this fixed before Windows 11 launch. If a fix is coming this month, is the fix just a month late? Or is everyone now scrambling to fix this?

I'm not going to go so far as to say it's 100% AMD's fault, but it's common practice for major component manufacturers, like Intel or Nvidia to work directly with Microsoft in optimizations. I'm sure AMD does as well.

Besides, AMD has much more to lose by not having this fixed.