Computer won't turn on properly. Power supply?

Webkiller8 · July 8, 2016

Hey guys.

A few months ago i upgraded my PC by getting another HD7970 (had 1 R9 280x) and running crossfire. I also had to upgrade my power supply to support both the cards and i managed to find a really good deal on a PSU, a Seasonic X-series SS-1250XM Active PFC F3. I can't quite remember, but it was around that time that (i thought) my power button on my case had stopped working when the computer is off, although it will still shutdown the computer if it is on. I assumed it was because of my motherboard being so small, and the second graphics card pushing on where the case power button is plugged in.

Since then i have just been leaving my computer on 24/7. But when i do have to turn it on, i have to slowly flick the power switch on the PSU on and off, which after a few (or many) tries would turn on the computer. Today i finally went to troubleshoot what was wrong so i could buy a bigger motherboard or whatever and found it wasn't the power button on the case. Removing the second GPU so the power button can be plugged in properly didn't change anything, and the power/reset buttons on the actual motherboard also do not work.

I'm assuming now that it is the power supply, but i'm not too sure as i know the motherboard is still getting power when the computer is off (the Ethernet port lights up), and when the computer is on, there are no problems are all. I can play very demanding games for 6 hours straight, and leave the PC on for over a week without it ever turning off. Another thing that might be important is when i put the computer into sleep mode overnight, it will at some point during the night turn itself off completely.

Here are the specs of the PC and if you need any more information, just ask.

Thanks.