Solorin344

Solved! A lot of the advice for this sort of problem was bent CPU pins, which pointed me in the right direction. There were small bits of debris on the motherboard pins, only very tiny bits in 2 places, but it seems that was enough to take 2 memory channels out! I used a very fine brush to clean the pins, and now all 4 slots work again. Best of luck to anyone who has this problem in the future!

Took the battery out, had to use a flathead to short it, XMP is off, still no post with those slots filled.

Yep, 2 + 4 are the priority slots so to speak, and it has been running fine like that for about a year, then a couple of nights ago it shuts down and now the system will only post if there are no sticks in slots 3 or 4 (currently using only 1 stick in slot 2).

My PC recently shut down randomly, after which it was fine for an hour or two, before shutting down a second time and refusing to post whatsoever. After disassembling and reassembling everything, I managed to get it to post with no GPU and 1 stick of RAM. I put everything back where it was supposed to be but it once again didn't post, just a black screen with the 'EZ Debug LED' flashing next to DRAM/CPU. After testing every RAM slot configuration, both sticks seem to work fine, and the PC will boot (currently typing on it) if slots 1 and/or 2 are being used, but any combination of

So I got it to post with 1 stick of ram and no gpu, which was a great sign. after assembling everything back together, it was displaying the same behaviour as before, black screen, debug lights on, only this time the light was on for ram, flicking to cpu and back to ram every few seconds. Long story short, after some testing, only slots 1+2 work for ram, with 1+3 and 2+4 or any combination of sticks that are in slots 3 or 4 not booting. I tried a CMOS reset, seems to have done not much. Any ideas?

Last night, my PC shutdown suddenly, and after turning it back on it was fine for an hour or two, then it shutdown again and now it won't boot. My motherboard (MSI Z390-A PRO) has a 'debug LED' feature where a light shows up next to what it thinks the issue is, and there's a light next to 'CPU'. When there's power to the system but it's not turned on, the CPU fan spins quite fast, with no other obvious activity (other than the debug light constantly on). Turning it on, the fan returns to a normal speed but it's just a black screen with, again, the debug light on. I've since di