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Journeyman III

Ryzen 9 7900X won't post

Just put the new PC together, booted up and light for CPU on the motherboard. I've built countless computers but never seen this issue with new out of the box components. Is that a pretty much guaranteed bad CPU, or could it be a motherboard problem? I'd appreciate insight on next steps, since this is all new hardware architecture I don't have spare motherboards/cpu's to swap, my other pc's are zen3.

3 Replies

Lack of info on rest of specs, and you might also want to ask on the motherboard maker support forum ?


Ryzen 5 5600x, B550 aorus pro ac, Hyper 212 black, 2 x 16gb F4-3600c16dgtzn kit, NM790 2TB, Nitro+RX6900XT, RM850, Win.10 Pro., LC27G55T..
Adept III

Can't you go to the shop and test it out there? 
Some motherboard take 5-10 minutes to get a FIRST post. Maybe this is the case? probably not because you have red light for cpu.

Adept II

What motherboard are you using?

If you motherboard has a BIOS flashback function or the ability to flash the bios without a CPU, it might be worth trying to flash to a newer version of the bios if one exists.

When i built my firs X570 system i remember having to clear the CMOS before i could get it to post.