I have the same problem on 7900X, sometimes the computer works for 5 minutes, another 2 hours, then the monitor turns off with the message Check signal cable. I replaced the RAM and the power supply, no change, I ordered a new motherboard, the computer has been working for 2 days without any problems, but when I changed the motherboard, I noticed 3 strange black pins on the processor. it looks like they burned out
