I upgraded from an i7-8700K to a Ryzen 7 5800X3D with a Gigabyte AB350N Gaming WiFi motherboard. The board supposedly has the latest BIOS version installed, but after reassembling everything, I get no display. The CPU fan spins, and the GPU gets warm even though its fans stay stopped in zero-RPM mode, but the CPU itself does not appear to heat up. I've tried different video outputs on the GPU and reseated the 8-pin power cable, RAM, and graphics card. I'm wondering whether the CPU or motherboard is faulty. I can clear the CMOS, test the parts in another AM4 system, and reinstall my original hardware to help isolate the problem.
2 Answers
Since the CPU isn’t warming up, reseat every power connection, not just the CPU’s 8-pin connector. Check the motherboard’s 24-pin cable, CPU power cable, RAM, and graphics card. Also inspect the processor for bent or discolored pins. Testing the CPU and board individually in another working AM4 system should identify which part is failing.
Confirm exactly how the motherboard BIOS was updated. The 5800X3D requires a compatible BIOS, and knowing that the board was tested with another CPU doesn’t necessarily rule out a BIOS or update problem. Also try clearing the CMOS before testing again.
The seller said they updated it to BIOS F54d and provided a BIOS screenshot. I cleared the CMOS afterward, but the system still showed no display.
I reinstalled my original CPU and motherboard, and the computer booted immediately. That points to either the replacement motherboard or the 5800X3D, so I’ll test each part separately.