A couple of days ago I decided it was time to replace my run down old computer casing with a brand-spanking new one. I did not replace any of the hardware, just re-seated everything and I am now having boot issues. Things appear to go sour when I attempt to boot with the cpu 12v ATX plugged in. Fans will start up and LED's will turn on and then just shut off in an instant and then attempt to reboot continuing the cycle. When I attempt without powering the cpu, things seem to power up smoothly. A couple of details I will include: When I first re-seated everything, I removed the cpu fan therefore requiring a new dab of thermal paste to be applied. I skipped that step at first and got the pc to boot to login before spontaneously shutting down. I figured this was simply because new thermal paste had not been applied and I'd just wait and buy some the next day. No cigar; after applying the paste I'm having the issue I am now. I've been through the checklist on this very site pertaining to boot problems and such and also tried to "clear cmos" multiple times although I'm not sure if it actually worked. Is there a chance not having that thermal paste for just a couple of boots caused something to fry? Or is my psu not powering the cpu correctly? How can I diagnose this problem and how will I know which parts need to be replaced? Here are my specs:
PSU - CoolMaster 750w
GPU - GeForce GTX 560
CPU - Intel i7
Mobo - Gigabyte GA-EX58-UD4P
PSU - CoolMaster 750w
GPU - GeForce GTX 560
CPU - Intel i7
Mobo - Gigabyte GA-EX58-UD4P