Hey, I just built a new gaming rig. I have: EVGA LGA 775 nforce 680i LT SLI Intel motherboard Intel Q6600 quadcore CPU Nvidia GeForce 8800 GT Video Card Western Digital "Raptor" harddrive Lite-on DVD-ROM/CD-RW disk drive acer 22" AL2223Wd monitor PC Power and Cooling Silencer 750 Watt power supply a Thermaltake armor case 4 Gigs of G-skill RAM(2 2Gig sticks) That's all the important stuff, not counting keyboard, mouse, etc. Now, I built the rig, and I plugged it into my monitor. Plugged the monitor power cord and the PSU power cord into my surge protector. I fire up both of them, and the rig runs for about 15 seconds(The fan runs, it makes little tiny noises, lights up), and then it shuts down. During this time, the monitor says no signal. I tried uninstalling all the ram, rebooting, and installing thhe 2 ram sticks 1 at a time, but that failed. Any ideas on what the problem might be? I'm stumped, this is my first build. What might be the problem. I highly doubt it's overheating already, after just starting up. Maybe I have a bad BIOS? I forgot to add, after it shuts off the first time, if I restart it, it runs for about 5 seconds. I am stumped. Any help? EDIT: I forgot, the lights that light up, are part of the MOBO, so I'm highly doubting the problem lies there. I have quite a few four pin connectors that are fairly large, but there's nothing to plug those into on the Mobo or anywhere...

You should maybe unplug everything that is not necessary for now (IDE cables, RAM, etc). Sometimes it won't start if something isn't seated properly. If you take out your RAM, and it starts, you should get a beep code or something. Make sure the connectors to your M/B (power, restart, LEDs, front USB etc) are all plugged in properly. Also, make sure you have both power cables hooked to the motherboard securely. In fact, the same thing happened to me when I forgot to plug in the other (4 port) power cable.

ok, I boot up and make it into BIOS, but now it still shuts off after about 15 seconds, so my MB is fine, since I can BIOS. I was able to speedread the BIOS, which itself shows up for about 5 seconds, and my RAM checks in,and it says F2 to go to set up, but I don't have a keyboard plugged in yet, and it would still shut down if I did make it to setup. Any thoughts? I plugged in another molex connector on my MB I somehow missed... I just need to figure out why this is going kaput after 15 seconds.

Check for short circuits. When I built my first pc, I accidentaly had a part of the mother board touching a metal part of the case, causing my pc to power down after only a second or two.

Of course, this probably isn't the problem, since your PC can go for several seconds without shutting down, but I'd still check it out if I were you.

Also, make sure the internal speaker is hooked up to your motherboard. If I recall correctly, sometimes the computer will beep an error code through this speaker if something goes wrong while booting.

after searching, it seems that this MB doesn't have a plug for a case speaker, nor an onboard one.... So I can't debug that way. I shot an email to a guy who works with computers around here, hope I can get a response.

um, have you even read the mobo manual? if there's no beep codes then there will surely be led codes described in the manual, if they don't already have in troubleshooting the cause of your actual problem.

the MB "manual" if you could call it that, was a little pamphlet that showed how to plug in the CPU, power, VGA, and peripheral cables.

haha, quality. tried googling it? i'd be surprised if there seriously isn't a speaker somewhere and matching pins for the connections. it's probably around the same place you have connected your power and reset buttons to. it'd be worth unplugging all of those little cable and starting again, as it's not hard to plug in 1 pin across from where something is meant to be and effectively create a type of short etc... perhaps you plugged something into the damn pc speaker + something else and so when the pc tries to beep at you it hits the power down pins too? food for thought.

[edit] http://evga.com/support/manuals/

reading what i assume is for your motherboard shows that you in-fact have an onboard pc speaker (i think they call it a piezo resistor or something similar), as well as 2 led's for post codes... is this right?

[edit2] well the led post codes are at the very end of the manual (page 112 onwards). seems pretty hard to mess-up the pins on this mobo as i suggested earlier. something to consider is clearing the cmos as instructed (turn off main psu power [unplug / switch at back etc], remove clr_cmos jumper, put jumper back on, turn the power back on... guess the jumper is just like a switch connecting to the cmos batter).

[Edited by - nb on December 14, 2007 11:48:52 PM]

Sounds like it could be the CPU overheating. Check to make sure you have enough thermal paste on the CPU and that the fan is plugged in to the PSU. Ditto w/ everything else, make sure all cooling systems are powered.

FlyingIsFun1217

I'd hate to be right about this, but in the pass every nvidia based chipset board that has started to do that to me has had to be RMA'd in the end. Usually the board will boot up and itll run for a bit then just auto shutoff means something in the southbridge is mucked up and its usually one of the add-in card slots (graphics slots usually for me). The board shutting off is because its trying to protect itself from a voltage spike its detecting in the southbridge - as a matter of fact I have an RMA'd Asus A8N32-SLI board sitting on my kitchen table i just got back today that was doing the same kind of thing your describing and it started happening after about a year .... maybe you'll be lucky and itll just be something else.

BTW: If your getting to the bios then that means that the memory, CPU and CMOS chip are working, as long as you have the fan plugged into the correct CPU slot and the bios is detecting a fan is plugged in. Even if the fan isnt working the heat sink will disipate enough heat to allow for the chip to run for a few minutes before overheating - which is why I think its a southbridge issue. Just my 2c.