01-09-2025 04:26 PM - edited 01-09-2025 04:49 PM
I built a pc end of 2023 which has worked great up to around late October 2024. Here are the specs:
7950x3d
x670e Hero
7900xtx
2x 4tb 990 pro nvme ssd
2x 32gb G.skill Trident Z5 Neo RGB
1x 3TB HDD
1x 860 evo 1gb sata ssd
I have my OS nvme ssd on m.2_1 (closest to the CPU), and had my 2nd nvme ssd in m.2_2. I had this for almost an entire year and it worked fine. So, somewhere around October, early November 2024, can't recall exactly when, the PC would sometimes not detect my m.2_2 drives on boot anymore, or after waking from sleep. Restarts would fix this, but not always - it was intermittent. Between the PC being built and this issue arising, I did nothing to the hardware it self, other than upgrading the BIOS as they came out (no beta builds).
At first, I thought the drive was dying. But when it detected it, it worked fine. Benchmarks and self tests all checked out. I did find a problem, the bootmanager wasn't on my OS nvme, it was on my sata ssd. So, I formatted the PC and I sorted that out, it's correct now. After this, I also decided to format my m.2_2 drive just to be sure. Full clean wipe through cmd diskpart, deleted partition, made a new one and formatted it. Didn't help. So, I rolled back to prior BIOS versions after reading some inconclusive info online, I tried 2403 and it didn't work. I could have gone back ever farther, but I didn't. I took out the sata drives, thinking some shared bandwidth issue, but it didn't help.
Finally, I did what I didn't want to and I swapped m.2_2 to m.2_3. And it works.........
I also want to mention that before and after each bios update / rollback I did a CMOS clear. I also reset default settings prior to.
I ran a benchmark on the drive, it's noticeably lower than what I recall it being when I built it. Current sequential read 6566 MB/s on m.2_2 vs 7437 MB/s on m.2_1 and sequential write 6433 MB/s vs 6962 MB/s. These tests are through samsung magician, the tests were the same then and now which is why I reference that. Not a horrible loss but would be nice if the write came back up a bit. IOPS relatively much closer, within margin of error.
So, here is the bottom line. Seeing as I did nothing to the physical hardware up to the point where it started failing m.2_2 drive detection except doing BIOS upgrades, is this a BIOS bug? I didn't do extensive testing on this, but each time that I disabled EXPO I stopped having drive detection issues. This was obviously not acceptable to me, which is why I ended up where I am now.
Last question. I know m.2_1 & 2 are PCIe5 and _3 & _4 are PCIe4. Is my drive's current lower performance values due to swapping to Gen 4 or is it something else? As I understand it 990 Pro's don't fully saturate Gen4, but I'd love some feedback on that.
So, I hope this gets attention. Here is a thread of other people having the same issue: https://forum-en.msi.com/index.php?threads/msi-mpg-x670e-carbon-wifi-expo-and-nvme-boot-drive-proble...
I'm very inclined to think there is a bug in the BIOS, something that affected drive detection and based on what I experienced turning off EXPO fixes it. Which sucks!
edit: I had the latest firmware from samsung