PCIe bug with M2_1 slot on X870E Tomahawk

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jlsmith.01712b902af

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So, the M.2_1 slot keeps reverting to PCIe 1 x 4 on a cold boot, sometimes just a reboot from within Windows. Manually setting it to Gen 4 or 5 within the BIOS will get it to run full speed until the next shut down/cold boot, then it's back to 1 x 4 again. Basically, I have to keep switching between gen 4 and 5 setting on every boot or it's stuck at 1 x 4. Auto is also broken. Samsung 990 Evo Plus 1TB.

I've seen another user on Reddit with the exact same issue. Same board, different drive. Anyone using this board, check your drive speed!
 
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Sharing a quick update that I updated to the latest 7E59v2A52 BIOS and now the Samsung 990 PRO is running at 4x4 PCIE and benchmark shows the expected speed.
I have also turned on EXPO with no issues.
1745741438651.png
 
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molino7 said:
Sharing a quick update that I updated to the latest 7E59v2A52 BIOS and now the Samsung 990 PRO is running at 4x4 PCIE and benchmark shows the expected speed.
I have also turned on EXPO with no issues.
View attachment 201350
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Just EXPO or have you done the changes shown in this thread (AMD overclocking settings) ?

You can definitely see when it was only running at Gen 1 x4 compared to now, hopefully it's fixed for good
 
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b933930151502d6 said:
Just EXPO or have you done the changes shown in this thread (AMD overclocking settings) ?

You can definitely see when it was only running at Gen 1 x4 compared to now, hopefully it's fixed for good
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Just EXPO, I am not interested in any other overclocking options.
And yes, now is noticeably faster when firing up a game, loading into a level, etc.
 
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46231157602dd said:
So i suggest someone should address this to MSI, and let them fix the description, hell even put a video for a better explanation.
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It should be sorted next working day
A request for it to be corrected was put in Yesterday.

For now, you're OK with Auto Setting and EXPO enabled, no need to adjust voltages unless you're overclocking or doing an undervolt
 
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46231157602dd said:
Here where my biggest problem with all of this is. Ryzen 7 9800X3D currently are burning all over the place of users. There is big threads on Reddit for it. Mind you, it's mostly on AsRock, as there is prolly currently 200+ cases, there is a good number of MSI, GIgabyte and Asus boards that this happen as well.
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That problem was solved long ago and is not likely to be a problem in any current Retail board being sold.
 
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Alan J T said:
It should be sorted next working day
A request for it to be corrected was put in Yesterday.

For now, you're OK with Auto Setting and EXPO enabled, no need to adjust voltages unless you're overclocking or doing an undervolt
Click to expand...

How about enabled CPU creation boost which set PBO to "Advanced" on x870-P , does this BIOS works?
 
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Updated to the latest BIOS and so far, knock on wood, everything seems stable, and I'm getting the proper 4x4 PCIE (both reported and tested with benchmarks) on m2_1.

One question - is it normal for BIOS settings to get reset to default after an update? I had to re-select all my settings after updating.
 
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jonamar157e02dc said:
Updated to the latest BIOS and so far, knock on wood, everything seems stable, and I'm getting the proper 4x4 PCIE (both reported and tested with benchmarks) on m2_1.

One question - is it normal for BIOS settings to get reset to default after an update? I had to re-select all my settings after updating.
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Yes, normally all settings are reset after an update, happened with my Gigabyte board as well
 
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Thanks for confirming. I've encountered it a few times over the past few months with this new build and I wasn't sure if I should be concerned or not. Like, is updating my BIOS eventually going to invalidate my Win11 license or something because MS is bonkers? I'm guessing it's just a heightened security issue or something.
 
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Does this bug effect the carbon x87e wifi too? I just cancelled my tomahawk order after seeing this thread, but I would be fine with upgrading to the carbon if it is not an issue with that mobo.

Literally not a single x87e mobo that is not having serious issues right now.
 
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rvillatoba14ec02d0 said:
You mean the M2_1 speed bug? Yes, it affects all MSI x870e motherboards. The latest bios (A52) fixes the bug for the Tomahawk, but I'm not quite sure yet for the Carbon. If you have a Carbon, you should install the latest bios (A33) and check whether or not it fixes the issue.
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Yes the M2_1 speed bug. Has it been fixed though? Reading through all the posts it looks like only 1 person said that they have not had the issue since installing A52 firmware, no one else has either confirmed or denied... and earlier MSI was saying bios update could not fix it and was having people RMA their motherboards...
 
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