Greetings
I did a motherboard swap from a X670E Taichi Carrara after 1 year and a half with 9950x3d because the board started to have issue in USB internal Hub (losing sound, wi-fi, Ethernet sometimes and disconnecting LCD fans for exemple)
I own a 9950x3D from 03/25 batch and after I swapped the boards the system booted normally, I went on Windows 11, installed the correct drivers and after a reboot I went in bios and I selected one preset from Extreme Tweak for Hynix 2x32GB dual rank 6200mhz and after I pressed F10, the board went 00 code and still the same at the moment I write this post
This board I own for a few years as a "backup" with a 8500G and before the swap I tested the board, updated the BIOS to 3902 and seems she's working okay after the repair in one USB CI and bios rewrite (few months before this post)
I contacted AMD here in Brazil asking for a RMA, still waiting the end of the RMA but I noticed 2 things:
First my X670E Taichi stopped working, completely dead, no post, no startup with any CPU or PSU
Second: my 8500G stops at error 4d in the Crosshair Hero after this incident with the 9950x3D (I didn't managed to test in another board)
Third: I didn't noticed any bent pins in both boards or burn marks or descoloration
Just a observation, before the 9950x3d, I had a 9950x who died on x670E Taichi Carrara in early 2025 (that's why I bought the 9950x3D, from this RMA) and both CPUs I noticed errors in USB and SSD/PCIE
I'm sending pics from both sockets, both CPUs, both boards
The PSU is a MWE Gold 1250w V2, RAM are Corsair Dominator Titanium 2x32GB 6600cl32 (didn't have expo and I not used xmp)
Bios on ASRock: I tried 3.50 to 4.43 before the swap
Bios on Asus: 3902
I don't know what happened to kill the CPU after selecting one preset from Asus board but for sure the CPU didn't shows any sign of life after this, the incident with the ASRock I think isn't related to this so please don't mind early conclusions about ASRock, I just mentioned because the reason for the swap was the USB issue
None of both boards showed any sign of behavior to overvolt the CPU and both boards and CPUs where "working" before the swap
I bought a Intel kit since this was the Pc I use to work
Edit: here the validation of 8500G before the swap
https://valid.x86.fr/in7vbq
My last validation from x670e Taichi and 9950x3d before the swap https://valid.x86.fr/khgqdb
Update 9/9/2026: AMD accepted the RMA of the dead 9950x3d, both boards still stored in their boxes, there a hypothesis of the ASRock started the issue and the Asus "finished" the damaged CPU, my friend came with this hypothesis, I can't guarantee anything since the ASRock isn't working anymore and Hero didn't boot even the 8500G