New build doesn't run

[dregs78]

Ugh. I built my new pc last night

RAIDMAX Smilodon ATX-612WBP (with 500W PSU)
Gigabyte GA-P35-DS3L (Intel P35)
Core 2 Duo E6750 (2.66GHz) Retail
EVGA 512-P3-N801-AR GeForce 8800GT 512MB
Seagate Barracuda 7200.10 250GB (ST3250310AS) 3.0 Gb/s
G.SKILL 2GB (2 x 1GB) 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400)

When I plug in the 4 pin ATX 12V the machine keeps on turning on and off with no video. When I unplug the 12V it powers up. The fan for the cpu comes on, same with the video card. But nothing on the screen. I think I've tried everything but was wondering if any of you had an idea. Thanks guys

 

[Harvey]

It sounds like either your power supply is failing, or something in your setup is shorting to ground, and your power supply protection circuit is shutting it down. Unplug everything, except your CPU and including your drives. Then, reseat your video card and RAM, and try to boot.

If it works, you've found your problem. If not, remove the mounting screws holding your motherboard to the case, and insulate it by inserting a piece of cardboard under it. Do this carefully so nothing else is shorting. Then, try to start it, again.

If it begins to try to boot, you've found the problem. Look at the case and the bottom of the motherboard to see if you can determine where it may have been shorting. Then, carefully re-install a couple of the mounting screws and try again. Keep adding screws until it all works.

I hope that helps. Good luck.

 

[dregs78]

Thanks bud. I tried removing everything one by one and trying that but it didn't work. But I think I'll give it a try and just take everything out and start from scratch. Did you think clearing my cmos would help? or hurt for that matter?

 

[dregs78]

I forgot to mention that for a while my power supply (or what I thought was the power supply) was making a load shrieking noise. I pulled out video card and reseated it and it went away. Don't know if that helps

 

[Harvey]

The noise could only come from a moving part, such as a fan or some wildly frying component. If you didn't smell smoke, it may have been something else. Did you check to see if anything else, such as a loose cable was rubbing against a fan, either on your CPU or your vid card?

If reseating the vid card changed it, you may fixed that problem, or you may have moved something else that was rubbing a fan.

If you're sure the PSU is OK, and you're still having problems, try isolating the motherboard as noted in my previous post.

 

[dregs78]

Ok so now the computer boots up. Sometimes it gets to the part where it starts to load the vista cd sometime it dies right before it. But either way the machine shuts down. Any ideas?

 

[robisbell]

which is it, 612watt or 500watt?

 

[jackschmittusa]

I wonder if your hsf is seated properly.

 

[dregs78]

It's a 600 watt.

 

[dregs78]

One of the hsf tabs is loose and it hard to get in. Could this be the culprit?

 

[jackschmittusa]

I would fix that and see.

 

[dregs78]

Anything else you fellas would try. I feel like I'm close to getting this fixed without putting anymore money out. Joy!

 

[robisbell]

that HSF has to be secuely locked into place if not, that's the main culprit.

 

[dregs78]

If I can't get the heatsink to stay in. Would anyone recommend a heat sink? Mine is the oem one from the cpu.

 

[dregs78]

Ok so I reseated the heat sink. It seems that whenever i leave the pc off for long peroids of time it stays up longer the next time i turn it on. I was able to install vista. But the box still reboots when it feels like it. Anymore ideas guys.