Computer will not boot 1

[markk85]

I have a very puzzling problem with my computer. I was using it the other day and everything was as normal until it suddenly switched itself off. I managed to switch it back on again a couple of times but only for about 10secs before it switched off again. I then flicked the power switch on the back of the power supply to see if switching the power off and on again would cure the problem. Now the computer will not switch on.

The only thing that happens when I press the power button is the cpu and case fan move a little as if they were beginning to spin but then nothing happens.

Can anyone help??

Thanks

 

[carpetbelly]

any strange burning smells? notice any power surges?

spec of machine might help down the line so prob a good idea to say what you have to.

Is it dusty in your machine preventing and fans spinning?

 

[muthabored]

For the short period of time that it does "come alive" do you hear any beeps or are there any LEDs (hard drive, power)? Try reseating your processor...if that doesn't work then your systemboard or power supply could be the problem. I would remove all components from the board except for the essentials (at least one stick of RAM, video card, etc) and see if the process of elimination doesn't fix it.

 

[markk85]

There are no strange burning smells and I haven't noticed any power surges. The fans were quite dusty but I have since cleaned them out so there is no dust preventing them from spinning.

Specs are:
Gigabyte GA-K8NS Pro Motherboard. (Socket 754)
AMD 64 3200
256MB Sapphire ATI 9800XT
1GB (2x512MB) Corsair Ram
400GB (2x200GB) Maxtor HDD
400W PSU
DVD, DVDRW, TV tuner

 

[markk85]

When I switch on the computer there are no beeps and no leds. The only thing that does happen is the fans move a little.
I have tried reseating the processor as well but I will strip the board down to the essentials to see if I can locate the problem.

 

[muthabored]

Hmmmm...could be either the board or the processor. I would imagine that if it were the power supply, the fans wouldn't react at all. Hopefully process of elimination (bad stick of RAM, etc.) will work.

 

[Xeroid]

Has the Power Supply got a fan ? If so does this spin up ?
If it doesn't I'd suspect the PS as first option.
Have you done a voltage check on the output pins of it, ie stuck a meter across the DC volts pins. No volts = no go.
If voltages are ok then your mobo is next likely culprit.

 

[markk85]

The power supply fan does spin a little when I press the power button.
I haven't got a voltage meter so I can't check that.
I did say earlier that no leds were on but I have just noticed that the ram led comes on when I press the power button.

 

[paparazi]

mkellaway
Most likely a failed power supply, often PSU's fail on one power rail giving the appearance of normal operation.
Is this a branded unit or one supplied with the case? if you have pulled out all addon cards and disconnected power to the CDroms and hard drives and it still does not POST it's very likely PSU.
Be aware that if the PSU has failed it may have damaged other components ie Hard drive/CDroms.
Reset cmos, pull off everything, leave bare minimum, short power header pins momentarily with a small flat blade screwdriver.
Still no post, try a PSU
Martin

Martin

We like members to GIVE and not just TAKE.
Participate and help others.

 

[keun]

I just put together a new system that would not boot, even with only the mobo and cpu. I tested the psu and thought it was good. One quick way to test the psu is to connect the two green wires. Just take a paper clip and stick it in the holes while holding it with some insulated needle nose. Your fans should spin. If they do not, you have a bad psu.
My problem was that my fans DID spin, but, little did I know, not fast enough, so even though I got some action the psu was not outputting the right amount of power.
I suggest going to the biggest retail store in your area and buying a psu, bring it home, try it out. If it works, order your new one on line and return the old once you get the new.

 

[markk85]

Thanks for all the help. It was the psu that was the source of the problem.

 

[PockyBum522]

Also be warned when shorting the psu, some will not spin the psu fan or generate any power until they have a load on them.

Also, on most power supplies I've seen, you short the green wire to ground (Black wire) and there's only one green.