*sigh* power up problems

[the whitman]

i wouldn't post this if i could have found something explaining the problem, but it's only similar to others..so here it is

i recently put my computer back together, and when i flip the switch on, it will stay on for half a second, and sometimes to about 30 seconds.

set up: amd athlon 64 x2 3800+
2x nvidia 7800gtx's
asus a8n32 sli deluxe
2x 250gig sata drives
650 watt coolmax power supply
2 gigs of corsair xms
a few lucky times i have been able to get to the bios and mess around for a few seconds before it shuts off, but really to no avail. the hard drives are from my old computer, but it won't stay on long enough for me to reformat them. my mobo doesn't beep at all, and the green power led wil stay on. i'm going to put it together on a bunch of anti-satic bags. any questions to help this problem will gladly be answered, and any advice would be appreciated. if this helps, sometimes when it's able to keep riunning, the fan on my graphics card slows down and then it will shut off

note: this same set up was used in my old computer except i just have a different motherboard and processor, and it ran like a champ

 

[Thelis]

It MIGHT be a RAM problem, but I am no too sure. Can you put it into another computer and run Memtest? I am almost definite that it isn't the problem, but it is never bad to be overly careful.

Are you sure the CPU is seated correctly? Are any pins bent or missing?

 

[the whitman]

yeah the cpu is seated just fine, and now i've gotten it to get past the logo screen and start detecting the hardware, but i've only gotten it to the very start of the windows format screen just once. the ram should be good, the sticks worked just fine in my last machine. sometimes my monitor will never come on either

just noticed that right before it dies, the fan on my graphics card will stop spinning

 

[Raffaz]

Have you fitted risers between the mobo and the case? It could possibly be shorting on something. Have you got another PSU that you can try?

 

[ssc456]

Have you fitted risers between the mobo and the case? It could possibly be shorting on something. Have you got another PSU that you can try?

thats wot my problem was.

and because i was such a novice i had to buy a new PSU.

but a person that has never made a mistake has not learned

 

[Rudster8161]

also try the setup without the second video card. maybe your PSU cant get enough juice one the 12V rails to get the whole setup up and running.

 

[lhuser]

It looks like the mobo shorting out. To try the PSU, try it on another PC and if you don't have another one, shrt the green and black wire. If it powers up, I'd look for your mobo shorting. Disassemble it and try it on a book. If it works, look where you missed.

You also nmeed to screw the risers, which are the gold things you screw in the holes, so your mobo stnads on that.

 

[the whitman]

ok so i've got beeps now.. i get one when i first start it up, and then 2 short ones before it shut down. i've tried everything here and it still hasn't fixed it.. i hope the beeps help

heres the sequences
no ram, no video card: 1 long beep, 2 short beeps
1 ram, no video card: 1 long, 3 short beeps
no ram, 1 video card: 1 long, 2 short
1 ram, 1 video card: 1 at start up then 2 short beeps

hope that helps

 

[the whitman]

new sequence.. 1 long 3 short after i put my wifes graphics card in it
fixed it.. it was a power issue