Windows 11 : L3 Latency after the last update (KB5006746)

1 : Anonymous2021/10/15 17:27 ID: q8t7ce
Windows 11 : L3 Latency after the last update (KB5006746)
2 : Anonymous2021/10/15 17:30 ID: hgrgzo6

The latency is good but the bandwidth is not optimal 🙁

ID: hgrqm2b

It still benches quite a bit below Windows 10 as well, let's hope AMD's updated chipset drivers will fix the rest.

ID: hgru70e


ID: hgrx4rg

Give it a few more updates and it should be better. Just being positive here. 🙂

ID: hgtmgxr

Granted I haven't tested on 10 with the latest Agesa update, but my 5950X has gotten higher cinebench r23 and time spy physics scores on 11. Only Aida l3 benchmark has been terrible.

ID: hgsuw3i

May be a stupid question but has there been any known issues with an Intel platform on Windows 11? Really want to go AMD on a new build but all this talk is scaring me...

ID: hgswosc

The right time to make 5-year decisions is not in the 1 month where everything is changing.

Wait and see.

ID: hgtg7ue

if you're talking pre-alderlake, their memory layout has been nearly the same for almost a decade so it's unlikely to run into any problems. alderlake is a big overhaul, though. I doubt it will be perfect day 1.

AMD already ran into cache problems with zen due to the unusual layout before win11 and they fixed it with updates. not sure why the bugs crept back in but it'll get fixed sooner or later.

ID: hgteo0i

I've had zero problems with windows 11 and I'm on the i9 9900k

3 : Anonymous2021/10/15 17:35 ID: hgrhmch

That’s good isn’t it?

ID: hgri0pw

I had ~1000GB/s R / W / C on W10

ID: hgrkg3x

Ahh so its not just the latency but the actual bandwidth too which is slower?

ID: hgufoo1

No, it's an insider build, not available for regular people. Your latency is as bad it used to be 2 weeks ago. OP is just clickbaiting.

4 : Anonymous2021/10/15 18:11 ID: hgrn161

God technology never ceases to amaze me, I mean, it takes light 1 nanosecond to travel about a foot in distance, insane.

ID: hgshqzn

It's 20cm in 1 nanosecond in an electric cable (or fiber optic).

ID: hgu20wu

Maybe they meant in vacuum?

5 : Anonymous2021/10/15 17:33 ID: hgrhdgg

Now we need AMD to release the updated chipset... wish they'd post it early.

ID: hgt7yds

They probably need to test this patch and WHQL validate which is why they are not doing the release now.

ID: hgrrxio

It will be release through windows update the 19th ... Check outside Reddit. The news is out like 2 or 3 days ago.

ID: hgrs9w7

That’s the update that was just pushed today for beta on windows 11. The other fix which is in the AMD chipset driver side is supposed to be release the 21.

Again, I wish AMD would just release their updated chipset drivers early.

6 : Anonymous2021/10/15 22:30 ID: hgsmetf

I got the same number for L3 cache--11ns! Down from 31ns. And there are more gains coming, apparently. Thanks for looking at it again...;)

7 : Anonymous2021/10/15 19:24 ID: hgrxldr

Damn these caches are fast.

8 : Anonymous2021/10/15 23:17 ID: hgss1iq

My write speed is still pretty low. Only 230gb/s, but latency is indeed fixed.

9 : Anonymous2021/10/16 01:26 ID: hgt70uu

These are my results, using Windows 10 (21H2), i also don't get 1000GB/s while using Windows 10 like you mentioned.

10 : Anonymous2021/10/16 09:13 ID: hgubkcl

But I thought intel was paying Microsoft to make AMD look worse with windows 11 so ADL reviews would be favorable???

11 : Anonymous2021/10/15 18:58 ID: hgrttp4


ID: hgtozfl

5000 ryzen series has identical IF inside as 3000 ryzen, both have the same issues with L3 in win11 and even zen+ chips also affected.

12 : Anonymous2021/10/15 18:33 ID: hgrq67g

Check your BIOS for update. AGESA V1.2.0.3 should be out...

ID: hgrr4xt has been out since October 1st for my Gigabyte Aorus motherboard. was in July.

ID: hgrykj7

i upgrade my bios to the last version available ( and got same results

ID: hgrrlqk

And? Patch C has been out for a while. Are you saying that KB5006746 + completely resolves the problem on Windows 11, both latency and bandwidth?

ID: hgrrtod

No. AIDA is indicating that OP only has installed.

13 : Anonymous2021/10/15 19:23 ID: hgrxcx0

I have a 3800X and just downloaded the update. Bandwidth is still lower than windows 10 but at least it’s showing in gb/s and not mb/s. My latency is 9.7ns so that is fixed at least. Now I just need to test some games.

Edit: Seems like CPPC or boosting is worse on this update. My CPU is boosting 25-50Mhz less than it normally would.

ID: hguf9j9

CPPC fix is coming in a separate update near the end of the month.

14 : Anonymous2021/10/15 22:41 ID: hgsnrmc

Can someone send me a video on how to do this benchmark for myself. I could not figure it out myself.

15 : Anonymous2021/10/15 22:47 ID: hgsoev8

So latency fixed and bandwidth better, but bandwidth still somewhat crippled.

MS better fix this in time for Alder Lake's reviews.

16 : Anonymous2021/10/15 18:33 ID: hgrq3nl

L3 latency is a lot less than what has been reported already. Memory latency and bandwith not so good either.

17 : Anonymous2021/10/15 20:56 ID: hgsadj0

Just benched my 3600 for the first time since building it 2 weeks ago and upgraded to Windows 11 before this news broke. My L3 was 30ns at 600 to 800mbs/s. I made an image of my SSD with Macrium prior to the Win 11 upgrade and I'm debating on restoring it.

18 : Anonymous2021/10/16 00:19 ID: hgszf2f

Anyone know if it's fixed for single chiplet 5000 series (5600X and 5800X)?

ID: hgt8m0f

Nice, seems fixed then

19 : Anonymous2021/10/16 01:44 ID: hgt90z2

My 5800x on the Dev branch (I can't get off it until I reinstall, really annoying) is fine.

I just updated from build 22471 to 22478, I did a before and after AIDA64 test.

22471 (dev-branch):

22478 (dev-branch):

And a typical "5800x" pre-Windows 11 result (not mine):

So a bit of an uplift in L3 write & copy, so I believe it could be patched in the very latest dev build? Anyone with a 5800x (or 5600x) on the non-insider preview build of Windows 11 able to post a bench of their results?

20 : Anonymous2021/10/16 06:06 ID: hgtyf43

why are my write and copy speeds slow after the update? they are still faster before update

before update

after update

ID: hgu6jh4

They're not. Before the update your write and copy speeds are in MB/s. After the update they are fast enough to be displayed in GB/s so they're faster.

ID: hgu7jhe


They are slow compare to other peoples screenshots.

Write / Copy Should be around 600GB/s for L3 cache on DDR4 3200.

Let see if coming Tuesday patch will improve more. People with DDR4 3800 CL16 are getting ~800GB/s

21 : Anonymous2021/10/16 07:30 ID: hgu4kwg


ID: hgu6fan

That's the same update that we're talking about here and as you can see it's not completely fixed. The screenshot is with the update you're talking about already installed.

22 : Anonymous2021/10/16 10:47 ID: hgui0lj

memory latency 63ns?? Are you running on XMP?

24 : Anonymous2021/10/16 11:31 ID: hguldm8

I hope Microsoft doesn't stop here because although the latency is fixed, the bandwidth is very low! AMD needs to be serious to Microsoft and push them to fix this issue!

25 : Anonymous2021/10/16 12:23 ID: hgupsve

Will be updating to 11 in January, that too if these issues gets resolved by then..

26 : Anonymous2021/10/16 12:45 ID: hgus004

Someone can explain how it ever possible that OS can mess up L3 performance? In my mind L3 is low level piece of cpu and dont have any modes which can be changed by software. Yes, MMU have a lot of modes and can affect caches as well, but win10/linux/freebsd/macos/etc all use protected mode and dont have such issues. Whats changed in win11?

27 : Anonymous2021/10/16 14:29 ID: hgv3gbw

Windows 11 is running in a virtual machine by default.

28 : Anonymous2021/10/16 12:49 ID: hgusf0h

I never get windows 11 updates unless it’s automatic and in the background?

29 : Anonymous2021/10/16 13:58 ID: hguzy3i

Wasn't 1000gb/s in l3 with 2ccd only possible with uncapped EDC in bios?

30 : Anonymous2021/10/16 14:07 ID: hgv0xqr

Work in progress.

31 : Anonymous2021/10/16 15:15 ID: hgv97ra

Running 5950x on a Dark Hero getting:

Read 973.29
Write: 895.12
Copy: 977.55
Latency: 11.0ns

KB5006746 installed

32 : Anonymous2021/10/16 15:48 ID: hgvdi2f



Better, but looking at the benches from others on this post, I'm kinda getting scared

33 : Anonymous2021/10/16 02:15 ID: hgtcgeo

Not acceptable.

Also, not surprising considering the history of Microsoft and Intel, and that Windows 11 was tested for 3 months.

34 : Anonymous2021/10/15 18:38 ID: hgrqvsf


35 : Anonymous2021/10/15 18:52 ID: hgrszkp

got it from Windows Update with insider program > release preview

36 : Anonymous2021/10/15 21:59 ID: hgsih84

how to do this testing? I went to aida site but do not see this interface

37 : Anonymous2021/10/16 18:26 ID: hgvzeel

it's in aida64 under Tools > Cache and Memory Benchmark

38 : Anonymous2021/10/15 23:59 ID: hgsx2fe

I got a 5600X also paired with 3600Mhz CL16 RAM but I get like 28GB/s on the memory write on windows 10 and the rest is the same as in this screenshot. I tried googling 5600X results and it seems this is normal, anyone know what's up with that?


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