My PC died.

getmore4less

Any beeps?

Movaraks

Wipe the RAM contacts with an eraser. Also, look if the capacitors in the power supply are swollen, it looks very much like the computer goes into a reboot because of the power supply constantly.

Neil_Jones

On the subject of "crappy" Corsairs...  There is one in my parents computer that I installed best part of a decade or so ago now.  It has lasted longer than the rest of the computer.

Anyway the OP's symptoms point to either a main board or power supply.  A second power supply (with anything "heavy" taken off) will show what the problem is.  If problem continues, board.  If problem goes away, original power supply has a fault (most likely a voltage rail failure)

IvanOpinion

While I am inclined to think power supply, you could try making sure all the connectors are in tight, even wiggle them about a bit and then push them home firmly.

CoastingHatbox

Based on 7 years maintaining a fleet of ~100 custom built PCs, Corsair PSUs seem to last pretty well.
BeQuiet and Antec PSUs that were used definitely have a shelf life.

If you were in my vicinity @LippyDoodle, I would look at it for you. I would first of all try flea draining power - unplug the PC a the wall and press the power button as if to turn it on. It might momentarily burst into life. Plug the PC back in at the wall and then try turning it on again.

If that didn't work, I would remove all the non-necessary components and then try and power it on, visually inspecting the motherboard for any bulging/leaking capacitors.

If that didn't work, I would test with a spare PSU.

I'm sure there's life in the machine yet and it sounds worthwhile fixing.