Help please: New PC shuts down after a few seconds

[Starscream]

OK, I finally got my parts together in my new PC and after powering up it will just shut down then turn itself back on. It does this in increments of about 3-5 seconds: Power on, fans spin up, 3 seconds later it powers down, then after another 1-3 seconds it powers back on. What's up?

I'm nearly positive it isn't grounding out at the MoBo (there are no screws behind it or the like), and everything minus the ram and drives are brand new.

The odd thing is that the last 64 bit board I was trying to use started doing the exact same thing after a day - power on, a few seconds pass, power down.

I've changed outlets thinking that may be it and that also didn't work. All my fans spin up and all drives come to life - it completely powers on.

So, I know it isn't my power supply since it's new, I know it isn't my wall outlets, I'm 99% sure it isn't grounding out, the CPU isn't overheating, everything is hooked up fine... but still no boot.

Here's the setup:

Asus A8N32-SLi-Deluxe socket 939
AMD Athlon 64 3700+ with fan and heatsink
Ultra X-Finity 500W power supply with dual rail
1GB (two 512s) Corsair (Samsung) PC3200 DDR400 RAM sticks with heat shields
Two (2) XFX GeForce 6800XTs running in SLi
80GB Western Digital hard drive
200GB Western Digital hard drive
Lite-On DVD-Rom
Sony DVD-R/RW combo drive
Ultra Wizard ATX mid-tower

 

[RichP]

OK, I finally got my parts together in my new PC and after powering up it will just shut down then turn itself back on. It does this in increments of about 3-5 seconds: Power on, fans spin up, 3 seconds later it powers down, then after another 1-3 seconds it powers back on. What's up?

I'm nearly positive it isn't grounding out at the MoBo (there are no screws behind it or the like), and everything minus the ram and drives are brand new.

The odd thing is that the last 64 bit board I was trying to use started doing the exact same thing after a day - power on, a few seconds pass, power down.

I've changed outlets thinking that may be it and that also didn't work. All my fans spin up and all drives come to life - it completely powers on.

So, I know it isn't my power supply since it's new, I know it isn't my wall outlets, I'm 99% sure it isn't grounding out, the CPU isn't overheating, everything is hooked up fine... but still no boot.

Here's the setup:

Asus A8N32-SLi-Deluxe socket 939
AMD Athlon 64 3700+ with fan and heatsink
Ultra X-Finity 500W power supply with dual rail
1GB (two 512s) Corsair (Samsung) PC3200 DDR400 RAM sticks with heat shields
Two (2) XFX GeForce 6800XTs running in SLi
80GB Western Digital hard drive
200GB Western Digital hard drive
Lite-On DVD-Rom
Sony DVD-R/RW combo drive
Ultra Wizard ATX mid-tower

I have not gotten into the dual sli's but I've heard of some issues.
Remove everything, HD's, optical drives, floppy so that ONLY the system board, cpu, ram are connected then power it up, you may get some beeps with no video card, ignore them, you want to see if it stays up, if that works plug in ONE video card, power it up, if it goes down swap video cards and try again.
You are trying to isolate the problem. I'd also try another power supply.
Where did you buy the parts ?
Also check your stand offs again, I generally only install the ones around the outside and ONE on the inside, generally as close to center as I can. I have seen and had those cause problems by touching a too close etching. I've even had to go so far as to use a shorter standoff and a nylon washer between the standoff and the MB on some of the feature packed mini boards.
One other thing you can do, pull the MB and PS out and put the MB on a cardboard box, you just need to 'touch' the power on pins in the header panel to power it up or like I do I have a loose switch. I've also had bad boards out of the box too, so if you get down to MB, CPU, RAM and it still pukes you more than likely have a bad MB..or cpu or ram, not had bad corsair memory, specially their matched pairs.

 

[Starscream]

Thanks for helping me out (again). I'll try those things and post back, but I have another question: the case had sort of built in stand-offs (raised "bubbles" in the MoBo mount), so I only had to use 2-3 real stand-offs. Could this be doing anything to it?

Oh ya, I got the parts from Tiger. They got the power supply/case bundle wrong twice, so I finally just got them to send me a PS. It may be bum, I'll just have to check it out.

 

[RichP]

Thanks for helping me out (again). I'll try those things and post back, but I have another question: the case had sort of built in stand-offs (raised "bubbles" in the MoBo mount), so I only had to use 2-3 real stand-offs. Could this be doing anything to it?

Oh ya, I got the parts from Tiger. They got the power supply/case bundle wrong twice, so I finally just got them to send me a PS. It may be bum, I'll just have to check it out.

Not seen these bubble standoffs. If it works OK out of the case I would use a piece of teflon tape on top of each standoff. As far as cases go the only ones I really use are antec, Chenming, LIanLi, Silverstone, Cheiftech which is just a rebranded antec pretty much. As for power supplies I now only use modulars which take them to the $125 entry level.

 

[Starscream]

Not seen these bubble standoffs. If it works OK out of the case I would use a piece of teflon tape on top of each standoff. As far as cases go the only ones I really use are antec, Chenming, LIanLi, Silverstone, Cheiftech which is just a rebranded antec pretty much. As for power supplies I now only use modulars which take them to the $125 entry level.

I've yet to try it out of the case. I'll do that tonight once I get off work. The Ultra case isn't that bad, I actually really like it. I would've loved a LianLi case, but at $120 a pop with no power supply, that's a little too much for me (at least right now).

 

[djblade311]

Rich's suggestions are good. I'd definitely try it with the MB out of the case (because MB mfr's will ask you to do it anyway for RMA). To me, it sounds like the Power Supply is DOA but do as Rich suggest powering up with one thing at a time and see when it decides to start. If there is too much draw on the PS, it will shut down.

 

[87manche]

check that hte power button isn't sticking.
It will cause the exact symptoms you have.
Unplug the power switch and trip it with a flat bladed screwdriver.
if you're not that brave, then take off the power switch and use the reset switch for power.

 

[Starscream]

check that hte power button isn't sticking.
It will cause the exact symptoms you have.
Unplug the power switch and trip it with a flat bladed screwdriver.
if you're not that brave, then take off the power switch and use the reset switch for power.

Ding ding ding, there's our winner. That's what it was (to an extent). The ground wire to my power switch had frayed and eventually seperated, causing the system to not even power on. We jumped it off and it works flawlessly. I'm going right now to mend it back together and strike up some BF2 in SLi, woo!

Thanks everyone for the tips and tricks!

 

[87manche]

welcome