I've been dealing with a frustrating issue where my PC keeps showing a Blue Screen of Death (BSOD) with the error code CRITICAL_PROCESS_DIED (0xEF). This started happening today after a week of stability, even though I updated my BIOS recently. Now, every time I power on, it goes straight to BIOS, and the only way to get out is by restoring defaults and rebooting. I've heard that I might need to reinstall Windows, but I ran a System File Checker (SFC) and it didn't find any corrupted files. For specs, I have a 5070 Ti graphics card, an R7 7800X3D processor, and an MSI B650 Gaming Plus WiFi motherboard.
3 Answers
Just to add on, you've mentioned the BIOS isn't detecting the M.2 drive where Windows is installed. That definitely points towards either a drive failure or a connection issue. Keep an eye on your stress tests for the CPU and RAM. If those are passing smoothly, then we could be looking at a hardware failure specifically with your storage.
It sounds like there are usually two common reasons for your system booting into BIOS: a failure to detect the boot drive or unstable hardware settings. The former could be due to a drive issue or problems with your operating system or motherboard controller. The latter often relates to overclocking of the CPU or RAM. If you're not overclocking, it might be an issue with the XMP profile, RAM, the CPU, or motherboard. Unfortunately, it's a bit of a maze, so if you can, have a local shop run diagnostics on it.
To troubleshoot the BSOD issue, you'll want to collect the dump files which can help diagnose the problem. If you can boot into Windows normally or even access Safe Mode, check for dump files in C:WindowsMinidump. If you find any, zip them up and upload to a file sharing site since some can be tricky. You'll want multiple dumps for a clearer picture, so if you only have one, make sure to configure Windows to create Small Memory Dumps as per this guide. That way, you'll get more useful data to analyze.

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