Help first time build...pc shuts down back on shuts down

jojo_61

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Nov 26, 2007
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I'm new at building so might not be familar with the pc language. so plase excuse me ahead time. Any assist greatly appreciated!!

Here's my parts:

Mobo Gigabyte GA-p35C DS3R
Intel E6850
MSI 8800 GTS 640MB
PSU Coolermaster Real Pwr 650
Corsair TWIN2X2048-6400C4DHX 2Gb (1gb each)
WD Raptor X (kinda nosy when its loading lots of scratching sounds)
Cm Stacker 830 Case

I think i plug everything correctly or at least i hope. Installed xp did my window udpates then asks my to restart. Restarted now it boots up for about 3secs or so back fan spins. processor fan starts to spin then shuts off. then repeats it self over and over until i turn off the power from behind. Nothing on screen just blank/black screen. Whats the problem? Can someone please help.

Is there a light indicator that when you plug when psu to the pc you know the mobo have power like intel mobo. there a green light to know everyting is good. Dont' have a clue if mobo is fried or not.

 
I'd take the case power switch out of the equation by unhooking it from mobo and then manually shorting the pins on the mobo to start PC. Probably not a bad switch but it could be and this is easy to rule out, sometimes they malfunction and you get a start, stop, start loop going like this. This is worth a shot but it's probably something else.

Could be bad power supply, bad mobo, or maybe a short somewhere. Try booting with nothing hooked up except power, cpu (and fan) video card and 1 stick of ram (only one) and monitor. Be sure all drives and usb devices are unhooked. Also re-seat video card and ram in this process and check and dbl check all power connections - main, cpu 12v aux, and video card.

If after this this same loop occurs then try again with a different stick of ram and move it to a different slot, if no help then try rebuilding same barebones setup outside of case, just in case something is shorting the mobo to the case or else a loose wire is pinched and shorting somewhere.

If this does not help try a different power supply, I always suspect the psu when something like this happens. and then lastly try a new mobo. They do go bad, even the new ones sometimes fail shortly after installation.
 

jojo_61

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Nov 26, 2007
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Thanks for your reply i'll try it tonight. A little lost about your first paragraph so might just have to skip that one. Not familar with what your saying about shorting the pin.
 

praeses

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Oct 10, 2006
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When you plug in the power switch from the front of your case, it attaches to two or more pins on the motheboard. The switch basically connects the pins together when depressed. To ensure that its not the problem as notherdude stated, disconnect the switch from the motherboard and short it temporarily by either sliding a jumper on there and removing it quicky (only needs to be connected for a brief second) or use the tip of a screwdriver or connecting it with a paperclip. I'm not familiar with that motherboard but some connect to an adjacent pin while the majority skip a pin. I would recommend unhooking the reset button as well, although typically if its sticking it will not power on at all.

Unless you have someone else to verify the sound of the harddrives in person, I wouldn't sweat it. Although they're not designed to emit that noise, the way they are designed causes them to emit that noise and its normal. They are "scratchy" sounding.

Considering that you are most likely not POSTing within those 3 seconds, I highly doubt your OS install is affecting it. Most likely something may be a bit loose or sticky inside that would have been affected slight movements. Perhaps a screw fell behind the backside of the motherboard?

I would try disconnecting everything you dont need to get it to POST first.

I.E. disconnect all the drives, the front panel connections to your case, any other addon cards if you didn't list them such as sound, even peripherals such as keyboard/mice. You do however need your video card/monitor hooked up.

If that fails, reset your BIOS which should be outlined in your manual. Most likely its not cpu/ram related as it usually will toss out a beep code providing you have the internal speaker hooked up (or sometimes the sound card works for onboard solutions) and it will remain on much longer than 3 seconds.
 


When you hooked up the little connectors from the case front panel to the row of tiny pins on the motherboard one of them was the power switch, it was marked with something like 'PS' and also the two pins it connected to on the mobo were marked with tiny letters indicating they were the power switch pins. If you simply pull the connector off the motherboard (pull the whole row of pins if this is easier, you don't need them to test) you can then start your pc my shorting together those 2 power switch pins on the mobo manually by touching them at the same time with a screwdriver os else putting a jumper on them.

This takes a bad case switch out of the equation.

and as prases suggested you ought to take off the 'reset' switch too.
 

jojo_61

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Nov 26, 2007
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just incase i'm doing something stupid...when you say paper clip into to the hole i'm not turn on the power right? I'm basically just connecting the ends to the paperclip..is this correct before i attempt. And what does it mean when i turn it off from the back and then all the fan does a quick twitch (back fan,video, cpu fan) couple of second when i turn it off. How can i tell if my motherboard is fried or if its my intel chip
 

Nastro

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Dec 4, 2007
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They mean on your motherboard (usually bottom right corner) there's some pins with connectors on them. The connectors are labeled for your case controls (power switch, reset switch, hdd light, etc.) Instead turning on your computer with the push button on you case, take the connector off the motherboard pins and touch both pins at the same time with something metal (paper clip is easiest). This will turn you PC on and if it still reboots constantly this will eliminate your case's power button as being the problem.