New PC Build - Turns on but then shuts off repeatedly.

[Keys]

Alright, so I'll make this as short as I can-

Bought a bunch of parts (all are compatible) from newegg to build a bitchin' new PC setup for a friend. Got the parts and the system wouldn't turn on. Sent back the power supply and the motherboard to be sure (free replacement, why not?), both were tested by newegg and had the motherboard replaced, the power supply refunded. I took the PSU cash and bought an ATX 800w power supply.

Now, the PC turns on briefly, the fans kick on, the cards and lights all come to life... for about a second, and then it turns off for three and then comes back on, rinse and repeat over and over again. WTF? So what's broken now?! [u]Here's the specs[/u]:

[b]Intel Core i7 920
2x Nvidia 8800 GTX
ATX 800w PS (the old was a Rosewil 850w)
Gigabyte EX58 - UD3R mobo
HT Omega 5.1 surround sound
2x 500Gb (1Tb) WD HDD
3x 6Gb Corsair DDR3 (6Gb) [/b]

So can anyone help me figure out what's wrong? The kid is waiting on this PC and i'm stumped.

And yes, everything is plugged in.

[i]Thanks guys![/i]

[JDK721v2]

Reset CMOS. What brand is the new PSU?

[Thor667]

Did you use standoffs when attaching the mobo to the pc case?
[img]http://70.169.170.235/acatalog/SCREWNUTMlarge.jpg[/img]

[lemonlimecom]

take out the 8800's and boot without them, then reinsert. For some reason that solved the problems I was having, which were similar to yours.

[Keys]

Figured it out.

When the old PSU went it tried to take down everything, luckily the expensive pieces survived with no damage such as the processor, 8800's, and HDDs but one of the DVDRW drives and two ram sticks went down in the fight. (the two ram sticks were what was causing the restarting) so I guess i'll send those back.

Everything was tested with ubuntu 9.04 live and is working.

Thank you very much guys.

[Second-gear-of-]

[QUOTE=Thor667;15990287]Did you use standoffs when attaching the mobo to the pc case?
[img]http://70.169.170.235/acatalog/SCREWNUTMlarge.jpg[/img][/QUOTE]

Will it permanently damage the computer if you don't install those?

[VladimirPutin]

AFAIK it can, not sure though.

You're just shorting out the system.

[Prismatex]

It is an incredibly dumb move to install the mobo without them.

[Brant20154]

[QUOTE=Keys;15992011]Figured it out.

When the old PSU went it tried to take down everything, luckily the expensive pieces survived with no damage such as the processor, 8800's, and HDDs but one of the DVDRW drives and two ram sticks went down in the fight. (the two ram sticks were what was causing the restarting) so I guess i'll send those back.

Everything was tested with ubuntu 9.04 live and is working.

Thank you very much guys.[/QUOTE]

Damn, I was too late, was going to say move the RAM around to see if that was causing it.:saddowns:

[Keys]

Alright, i've got a new problem!

So after having it all bench setup (not inside the case) and having gotten everything to work I decided to hook it up to the case and run it like it's supposed to.

Everything plugged in, situated nicely, and ready to go.

Power turns on for a split second and then goes off, comes on, goes off, comes on, goes off, comes on, goes off, etc etc etc. It does this infinitely a sort of * - * - * - * - * - *
The fans and lights kick on for each split second. It's a very steady pulse.

I removed the RAM, optical drives, HDD, and disconnected everything from the case (though GPU / CPU / Sound Card are still attached. Removing them now.)

What would be causing this? I think I lost a screw earlier, but I'm pretty sure I got it, so I don't think it's lodged in the case- Would a loose screw cause this sort of thing?

[Collin665]

The only time this ever happened to me was when I had three fans all daisy chained together and for some reason my corsair 750 watt didn't like it.

[ThePunisher1]

[QUOTE=Second-gear-of-mgear;15992345]Will it permanently damage the computer if you don't install those?[/QUOTE]

Yes, if your case is made of conductive material then its basically jsut going to fry your motherboard and possibly kill your other components.

[Roast Beast]

[QUOTE=Keys;16003471]Power turns on for a split second and then goes off, comes on, goes off, comes on, goes off, comes on, goes off, etc etc etc. It does this infinitely a sort of * - * - * - * - * - *
The fans and lights kick on for each split second. It's a very steady pulse.[/QUOTE]

I've run into that problem before with my Gigabyte mobo, I'm afraid to say I don't know exactly how to fix it. Letting it sit without power + removing the CMOS battery was necessary to fix it the first time, but I've encountered it several times since then and simply unplugging it for a minute got it working again.

[Phreebird]

[QUOTE=Second-gear-of-mgear;15992345]Will it permanently damage the computer if you don't install those?[/QUOTE]

Yes

[Elmand]

[QUOTE=Roast Beast;16003613]I've run into that problem before with my Gigabyte mobo, I'm afraid to say I don't know exactly how to fix it. Letting it sit without power + removing the CMOS battery was necessary to fix it the first time, but I've encountered it several times since then and simply unplugging it for a minute got it working again.[/QUOTE]

You know mate, you just solved my problem I've been having with my GB motherboard. Thanks for that, but when I put the cmos battery in again the first time it was doing the same thing again, any way of sorting this?