View Full Version : Computer turns itself off after 15 minutes

03-03-06, 08:37 PM
I recently replaced a motherboard in an older computer. Specs are:

AMD 2800+ 133 FSB, 512 RAM, Radeon 9800 Pro, Foxconn K7S741GXMG-6L motherboard.

I replaced the motherboard, and tried to turn the computer on. At this point, I was using a 350 Watt coolmax power supply. The computer would turn on for ~ 3 seconds, and then shut itself off. For whatever reason, if I unplugged the connector running from the front-mounted power switch to the motherboard after the computer turned on, but before it turned itself off after ~3 seconds, the computer would post and go to windows.

After using the computer in windows for a time, it shut itself off. After two or three times of it shutting itself off in windows after ~15 minutes, the power supply made a popping noise and the inside of it smelled like burning.

I tried switching power supplys, and although it starts up using the aforementioned method, the computer continued to turn itself off after ~15 minutes.

What is causing my computer to turn itself off after such a short amount of time?

03-04-06, 12:25 AM
Id say your CPU is overheating or your motherboard is dieing. Go into your BIOS setup and sit at the health\temp screen and watch your CPU and case temperatures. Let it sit for a long time (while watching it) and see how high the temperature goes.

If it doesnt appear to be doing anything out of the ordinary (your CPU temp should not get over 45-50C... thats hot), load windows and let it do its thing and wait for it to turn off. When it does, immediately turn it back on and go back into the bios and check the temperatures again. If they are still normal, you're most likely looking at a bad motherboard, but it really could be anything.

Let us know what you find out, I do this crap all day at work, so I'll help you figure out the next step.

03-04-06, 08:51 AM
I tried just watching the computer's temp in bios. It got to around 53 degrees C and then shut itself off. It wouldn't let me turn it on for about a minute, and then I when I did turn it on, it only lasted for 2 or 3 minutes as opposed to the 15ish from before.

03-04-06, 02:58 PM
could be power instability. newer mobos use more power. hows your 12V rail(s)?

(also, plz post your specs in your sig :) )