I bought this second-hand PC less than a month ago, and it has been shutting down completely while I'm gaming. After some restarts, the BIOS itself freezes and the keyboard stops responding, so I can't navigate the firmware setup. Windows also only reports that it was not shut down properly and doesn't create a crash dump. The system uses a Ryzen 7 7700, RTX 5070 12GB, ASUS PRIME A620M-K-CSM motherboard, 16GB DDR5-4800 memory in two 8GB sticks, a 1TB Gen3 TLC SSD, a Cougar 750W 80+ Bronze power supply, a Cooler Master Hyper 212 3DHP Black cooler, and Windows 11. Since the failure can occur outside Windows, I suspect a hardware, power, memory, or motherboard problem. What should I test first to determine whether the PSU, motherboard, RAM, GPU, CPU, or another connection is responsible?
5 Answers
Start with a baseline configuration: clear the CMOS, load default BIOS settings, and test with only one RAM stick installed. Let the system sit in the BIOS for a while to see whether it freezes even without Windows running. Then check CPU temperatures, test the second memory stick separately, and reseat the motherboard, CPU, GPU, and power connections. If possible, remove the RTX 5070 and test using the Ryzen 7 7700’s integrated graphics. A known-good power supply would also be an important comparison. An abrupt power loss usually won’t produce a Windows dump, so this points more toward hardware or power than a normal driver crash.
That makes sense. I’ll start with the CMOS reset and single-stick memory testing before changing anything else.
Because the motherboard doesn’t include a built-in diagnostic display, a compatible POST diagnostic card could help show where startup is hanging. It’s not the first thing I’d buy, but it may be useful if the basic isolation tests don’t reveal anything.
Check Reliability Monitor, but don’t be surprised if it only shows that Windows was not shut down correctly. That message confirms the system lost power or crashed too severely for Windows to record a useful dump, but it won’t identify the failed component by itself.
Inspect how the graphics card is mounted. If the case uses a vertical riser, or if the card is sagging heavily, the card or its connector could be losing contact with the motherboard. Remove the riser if there is one, support the GPU properly, and test the PC with the motherboard lying flat if practical.
Find the exact model number of the Cougar power supply rather than relying only on the 750W and Bronze labels. Cougar has both decent and poor-quality units, and the specific model matters. If the BIOS still freezes after resetting the CMOS and testing the RAM, temporarily trying a reliable, known-good PSU is one of the strongest ways to narrow this down.
Unstable memory settings can make the BIOS appear frozen too. Clearing CMOS and leaving the RAM at safe default settings is a good first test before enabling any memory profile or tuning.