Question System randomly freezes under load and will not recover


Jun 13, 2013
I have an issue where my computer will completely freeze under load (e.g. playing video games), and will not respond to Alt+Tab, trying to open task manager, or any other input and will require a hard reset. This doesn't happen during light use or when idling but does also happen when stress-testing my CPU. When my computer freezes, the audio cuts out and will never recover. In the past, I've had various BSODs, but over the past several weeks it's simply been freezing. I can confirm that this happens due to load as running a CPU stress test will cause the system to freeze within 2 minutes on average, every single time. I have not had any hardware changes. My system is around 7.5 years old and still has the same thermal paste from when I built it. I've cleaned out my GPU and CPU cooler recently with compressed air, but have not experienced issues with overheating or thermal throttling.

Could this be a CPU or VRM issue? A few people I've spoken to have mentioned that the CPU could be on its way out, especially due to my having overclocked it in the past and possibly damaging it in the process. Another has mentioned that the VRM on my motherboard could be faulty, not being able to deliver sufficient voltage under load which could cause the freezing issue.

I've tried a few different solutions, including:
  • Clearing my CMOS by removing my motherboard's battery
  • Ran chkdsk in Command Prompt on all drives, no errors found
  • Ran sfc /scannow on my system drive, it reported corrupted files the first time but has not had any issues since
  • Updated BIOS to the latest version, restored all settings to factory default
  • Re-installed GPU drivers in safe mode using DDU, re-installed using GeForce Experience
  • Updated GPU BIOS to the latest version using nvflash
  • Trying a different GPU of the same type (GTX 780 Ti) to see if there were any changes (none recorded)
  • Diagnosed RAM using memtest86 with 4 passes, reported no problems
I've had issues with BSODs over the past 3 years or so, where sometimes I would crash under load in games, but only in the past several weeks have I had hard freezes instead. For context, I attempted OCing both my CPU and GPU around 3 years ago but eventually reverted this as I wasn't sure of the profiles.

Some BSODs that I've encountered are:
  • IRQL_NOT_LESS_OR_EQUAL (citing nvlddmkm.sys)
However, these have largely disappeared and have been replaced with a hard freeze since updating my BIOS. The BSODs used to happen occasionally, whereas the hard freeze will now occur every single time my PC is under load, e.g. playing games. On occasion, after rebooting my PC from a freeze or crash, I'll receive the "Overclocking failed!" message, despite not having a CPU OC profile or RAM XMP profile. I've tried overvolting my CPU today from its stock value of 0.992 to 1.2V, which seemed to remedy the freezing issue and was instead replaced with BSODs (write to read only meroy and page fault). However, freezing occurs instead when running a CPU stress test.

System specs:
  • i5-4670k @ stock clock (3.4GHz)
  • EVGA GTX 780 Ti Classified (stock core and memory clock)
  • 2 kits of Corsair 2x4GB 1600MHz dual-channel RAM (16GB in total)
  • Asus Z87-A motherboard
  • Windows 10 64-bit, version 21H1, OS build 19043.1348