[Solved] Weird Boot =(

Hey everyone,

I just recently completed my first build. specs are as follows:

NZXT Phantom Case
i5 2500K
ASUS P8Z68-V LX Motherboard
G.Skill Sniper RAM 8 Gb
Intel 320 series 80 Gb SSD
WD Caviar Blue 320 Gb HDD
EVGA GTX 560 Ti DS SC
Corsair 750W PSU

It booted up on the first try and booted great for the following week or 2.
Then I installed Ubuntu as a secondary OS (I can choose which to boot into upon start up) and things were still fine for the couple boots after that.

Then, out of the blue, I turned it on, some of the fans didn't come on, and it shut itself down after about 5 seconds. I tried to restart and all the fans started but I got an error screen saying the the O.C. was not functioning properly, or something like that. I'm assuming that its talking about some sort of over clock but i am not overclocking my system anymore then what the i5-2500K does on its own. I got it to boot up after going through the set up menu and everything was working fine once i got into both Win7 and Ubuntu.

but everytime, now, when i start it up, all the fans spin up, but the whole thing restarts after about 5 seconds and on its second attempt it boots perfectly normal and once i get into either OS everything functions correctly.

I have no idea whats going on, or if its serious or what. No LEDs flash on my motherboard and there are no beeps either. Any help would be greatly appreciated!

Thanks!

Is your computer hooked up to a UPS? Oddly enough this actually happens to me too. My system is overclocked however (i5-750 @ 3.8 Ghz) and usually it happens when I first start it up after also first powering up the UPS after a while. I usually keep it off when I'm not going to be around so that it doesn't try to provide backup power to things I'm not using. I accidentally left it on one time for a week when I was gone and when I got back and powered up the desktop it booted perfectly fine first try. Not sure if it's anything serious as I've yet to experience anything bad, but just my personal experience of a similar issue.

Best answer selected by olso5629.