Computer not POSTing after rebuild

davidsmith2020online · July 20, 2021

Hi everyone. I recently replaced a failed AIO (Antec Mercury 240mm) [which has never been brilliant] with a (new) trusted Coolermaster Hyper 212 Black. During the machine downtime of about 1-week I took apart the computer entirely and reassembled it today, when my new cooler arrived. The reason for the replacement was because the AIO was loud, and not very efficent. I began to reach thermal throttling limits in the summer heat; and after remounting it (with fresh paste) about 3-4 times I decided it was bust.

I then disassembled the PC. This includes CPU in the socket, all drives, modular PSU connections: everything. I'm very troubled as when I reassembled the machine today I'm getting no response from it. No display output (through DGPU and onboard), no KB/M response (lights/power off) though when I press the power button all fans spin. I have tried my hardest to diagnose the fault. So far I have cleared CMOS, tried various memory configurations, removing drives, removing the GPU, and powering on without a CPU to try and correlate the problem. (No CPU = GPU fans spin endlessly. CPU in socket = GPU fans turn off and idle) Nothing in my head adds-up or makes sense to what the fault could be. I am careful with my components though still fear a CPU or Motherboard failure.

Any more diagnosis tips would be greatly appreciated as I try and resolve this problem. Thank you so much for understanding and I hope to get some feedback, so don't hesitate to DM me or reply to this message as all help is massively appreciated.

System Specifications: