Computer not Booting after unexpected turn-off.

[carl_palmqvist]

I have a home built computer that had been working for around a year with no problem. A couple weeks ago i got the problem where to computer started but didn't boot, which i fixed by replacing the Motherboard and the CPU. But yesterday, just before BF4 was about to release, my computer unexpectedly turns off, and immediately tries to turn on again. But after about half a second the computer died again. Then i pressed that start button and nothing happened. I waited for a while and tried again, it started, then half a second later it shut off again. Now, a day after, the computer won't start at all. I have tested the power supply manually, and all the pins show the right voltages and fans start when i do a force start on the power supply. I have tried clearing CMOS and it did not work, and i highly doubt its the motherboard, since its only 2 weeks old. Same goes for the CPU. The graphics card i know for a fact works. I'm struggling to loacte the problem, because the PS works on its own, but when i plug in the 8 & 24 pin connectors, it seems to not respond when i press the on button.

My PC specs are as follows:
MSI Z771-GD55
Gigabyte Geforce GTX 680
Intel i7 3770k
2x8 GB ram G-Skill
Corsair HX 750

 

[Kelthar]

Unseat the RAM and reseat it.

If that doesn't work, seeing as you're unable to clear CMOS, I'd place my bet on the motherboard being dead (since the PSU appears to be working). Also, try searching for signs of a shortcircuit (burnt area, burnt smell, anything like that). If you find any, the component with them is damaged.