Computer starts then turns off within a couple of seconds

[mrpete]

Hello,
Basically, i took off my heatsink/fan, had some trouble fitting another hsf, then decided that i would put my old hsf on. So i put it on, plugged in the wire, and now my computer won't work.

It turns on for approx 2-3 seconds. In all this time nothing is displayed on the screen, but it changes from the "No input signal" (to just a blank screen). this is normal, as normally after a few seconds it changes to the asus a7n8x-e dlx splash screen thing. After the 2-3 secs, the computer turns off. If i try to turn it back on, i have to turn the PSU I/O switch off then abck on, then i can turn the computer back on using the normal case switch.

my specs are -
asus a7n8x-e deluxe
asus 9600xt
barton 2800
sony cdrw/dvd
generic fdd
2x512 mb ram - corsair and another make i always forget the name of,but it isnt generic
a 56k modem - never use it any more
and a 400w psu that came with the case.

what shall i do?
thanks

[schmunk]

That's the mobo's overheat protection kicking in - there's something wrong with the HSF. Try refitting it (make sure you get the notch on the right side).

[herulach]

You put grease on when you refitted it yes? And cleaned teh old stuff off? Wha exactly was the problem with the new one? It might be worth a visual inspection of the die, axps are notoriously fragile.

[Hans Voralberg]

Seems like a overheating thing to me, check the HSF.

[Nox]

I had similar with a PSU overheating in an old systems a few months ago. Would sometimes last 3 seconds, sometimes last 10 seconds.

Nox

[Voodle]

[0iD]

Sometimes if the cpu fan is connected to the wrong header or you're using a fan with a molex conn, the mobo will think there's no cooler fitted, thus refusing to start. Usually this feature can be disabled in the bios.

[mrpete]

Hello,
Today, i took the heatsink off, cleaned both the heatsink and cpu, and put some new thermal paste on the cpu. The heatsink was then put back on, and the cpu cable put onto the cpucooler header thing. The fan works (ie it spins) and it is deff. the right cpucooler header (rather than for example a case fan header).

However, it still won't owkr. Now though, it doesn't turn off after a few seconds. It just makes the sounds like the hdd whiring round, as it usually does. Nothing is shown on the screen at all (and yes...it is plugged in). I removed one memory stick (it looked a tiny bit like it was out of place, even though i don't think it was). it still doesn't work.

Anything you can suggest?

[0iD]

Dead CPU/dead Mobo. Got a spare mobo you can test the cpu in? or a friend that has?

[Jonny]

DO NOT take what I say as definately appropriate for your own situation, but my mate's PC was turning off after a couple of seconds, and then when we finally sorted it (by reseating heatsink + general fiddling), nothing appeared on the screen. Turned out that the Mobo had been turning the system off to prevent overheating, but simply by repeated turning on and shutdown under hot conditions we had killed the processor anyway, hence the blank screen. Do you have another motherboard to test the processor in? And did you check it for burns when you reseated the heatsink?
EDIT: Also, test your CPU in another Motherboard, not another CPU in your Motherboard, as sometimes it is the Motherboard that kills the CPU. and you don't want to kill two.

[mrpete]

I have some mates that have a similar socket cpu/mobo, but to be honest, the chances of them trusting me to test something on their computer is low. None of my friends would even open up their case, so no chance of removing their cpu etc lol.

I am thinking of going 64bit... What would be the cheapest, but still decent (ie have 5.1 sound, sata etc -all the features of the a7n8x-e dlx-), 64bit motherboard/cpu worth going for? I don't think i hane enough money though to do this (called up bank 5 mins ago, as i lost my debit card over the weekend, and i only have about £80 in there, and lessthan half of that in cash in my room).

[wakkyman]

In reguard to your pc restarting after a couple seconds. This can be cause by many different faults. I personally would look at the power supply first rather then your cpu, mostly because in the event of somthing wrong with your cpu, your pc will not start at all. I had the exact same thing happen when i changed my mobo to a new tower. What happened was there were 2 plugs comming from the power supply, the standard mobo plug and another 4 prong plug, that plugged in next to the cpu. I had not experienced this before, maybe its common in newer pc's but i mostly messed around with older ones. I'm not saying this is your solution but it is one of the possible outcomes.

[Jonny]

I think he'll have given up hope if he hasn't got it sorted by now, to be honest.

[DratUK]

I think he'll have given up hope if he hasn't got it sorted by now, to be honest.

Considering the date of the post
01-08-2005, 01:28 PM

[wja96]

I would have though he should be listening for beep codes - no? I think alternating hi/lo continuous tones are the signal for a bad CPU.

But if there isn't a bad date issue here, then I suspect he's sorted it out already!