Hardware PC is stuck in boot loop; check power supply connection.
Hardware PC is stuck in boot loop; check power supply connection.
Hello everyone, I've been facing a problem with my PC recently. It gets stuck in a boot loop after turning it on. During the POST process, it briefly displays the boot logo but doesn't reach Windows. The last observed codes range from 99 to A0, with A0 likely being the final code during POST before the OS starts. Code 99 means 'Super IO Initialization,' which could suggest a hardware issue or insufficient power supply. I've tried several fixes: unplugging peripherals, disconnecting the GPU, removing all SSDs, booting with one RAM stick, changing its channel, testing another RAM stick in a different channel, and even removing the water pump and fans. Clearing CMOS didn't help either. It seems the power supply unit might be the culprit. I checked its self-test feature—pressing the button and seeing the LED green indicates everything is functioning properly. If the PSU is disconnected, the test passes. Connecting the 10-pin ATX cable fails the test, but other cables still light up correctly. I'm unsure if a short circuit on the motherboard or a faulty cable is the cause. My specs are: ROG Maximus X Formula motherboard and Corsair AX1200i PSU. Operating system is Windows 11 64-bit. Appreciate any advice!
You're asking about the exact moment the 24-pin ATX cable is connected and what signals its proper functioning. It's important to confirm whether the connection happens only on the motherboard or if the cable itself can fail under certain conditions. If the PSU passes self-test without the cable plugged in but fails when it is, it suggests a hardware issue with the cable. However, if the test succeeds with the cable connected but not on the motherboard and then fails when connected to the board, the problem likely lies with the motherboard. Clarify both the connection point and the failure context for a precise diagnosis.
The 24-pin ATX cable splits into separate connectors at the power supply end—10 pins and 14 pins—and also branches to the motherboard connector. The 10-pin side seems to trigger a self-test failure when connected, while other configurations resolve the issue. Your experiments support this conclusion.
Yes, if connecting the 10-pin to the PSU causes failure, the issue likely lies with the cable. Another approach could be connecting the 24 and 8 pins to the motherboard while leaving the 10-pin disconnected from the PSU side. This should resolve the problem.
It seems the cable replacement didn't fix the issue, and the same challenge remains. I've changed the cooling paste for both my CPU and GPU recently. The system has been stable enough to suggest a possible reassembly error, though the CPU was reinserted yesterday without resolving it. I plan to disassemble the GPU this weekend to check for problems. Any suggestions?
You can't share bios, and even with just CPU and RAM it didn't work.
Yes, that's a good idea. I'll verify the status LEDs on my motherboard along with the Q-codes later today to determine their relevance.
The video shows the status LEDs updating in sequence: CPU, DRAM, VGA, then BOOT. Once the BOOT LED turns green, the system powers off and restarts. The manual suggests the components pass POST, but since the loop keeps repeating, it hints the power supply might be the issue.
I swapped out my PSU and it fixed the issue. Appreciate the assistance from everyone!