I just upgraded my cpu and now when i try booting my pc all the fans spin up and all the lights turn on ans thrn everything turns off a split second later. I put the cpu in correctly for sure so idk what to do.
This is usually caused by a component shorting the board. If you really are sure that the CPU is properly installed, could you try going back to the older one? There's a chance that your new CPU is bad and that it never worked in the first place. Check the motherboard for bent pins or anything of that sort. Also, make sure that the PSU is working on another computer as this could also be a cause for your problem, but if the only thing you did was replacing the CPU, my guess is that either you damaged the board while installing it or the CPU is dead.