I'm really stumped here. I've been using my 9800X3D along with G.Skill Royal 48GB of 8000MHz RAM for almost a year without a hitch. I replaced my old MSI Godlike motherboard under warranty last December with a Godlike X, and soon after, I started experiencing random freezes and reboots while gaming, particularly in FFXIV, and sometimes even while just idling with my browser open. There are no BSODs or error codes logged, just unscheduled reboots after a couple of days. I've replaced almost every component: the old GPU, PSU, SSD, and even did a clean installation of Windows 11, but nothing seemed to help. I ran Memtest86 and it showed both RAM sticks were fine, but I've only ruled out the CPU, which I've noticed has had some temp spikes when launching games. At this point, I'm starting to wonder if the CPU is the issue since I can't pinpoint what's causing these freezes. Is there a possibility that the CPU has somehow become unstable just like that? Any advice would be appreciated as I'm about ready to swap out the CPU but am worried it won't solve the problem!
4 Answers
I had similar freezing issues without any clear error codes showing up in the event viewer. Curious, did changing your Windows version have any impact? I had the same experience after I upgraded, but an older version ran smoothly. Maybe this is a Windows-related issue that’s causing your headaches.
Have you thought about lowering the memory frequency to around 6000MHz? Even if Memtest shows both sticks of RAM are fine, running just one stick might help isolate the problem. Also, check out the Windows application logs; they might give you a clue as to what's happening, especially if there are any warnings or errors that you missed before.
There might be a chance that your RAM is overheating due to airflow issues when gaming, especially if the GPU is blowing hot air onto them. I recall Wendell from Level1Techs mentioning that high temperatures can cause DDR5 instability. Just keep an eye on temperatures during gaming as overheating RAM can lead to all sorts of issues.
I dealt with a similar issue with less powerful hardware, and reseating cables and components helped resolve it. My system would restart unexpectedly like someone cut the power. I thought I fixed it by reseating my RAM and even noticed that one of my M.2 drives had sagged. It’s hard to tell what the actual fix was, but since it hasn't happened in months, it might be worth thoroughly checking your connections or seeing if the PSU is delivering consistent power.

I suspect it might be a Windows 11 issue, too! I've been using 25H2, but I don't remember what version I had before. I'm thinking about returning to an earlier version to see if it makes any difference.