Member Avatar for just_humes

When the power button is pressed the computer seems to be running fine. The power and activity lights both come on, the fans start and the hard drive and cd roms both start up. After that there is nothing, doesn't even come close to loading the OS. There is no beep and the floppy drive doesn't flash. The computer just seems to stall there for an eternity. The monitor doesn't show anything, just stays blank and receives no signal. Nothing internally was touched. It was working one night and the next morning it was goosed. It has booted very rarely, after countless attempts, but always shuts down randomly.

Is there anything worth trying or should it be launched into the nearest skip?

Cheers

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For (and others seeing a box that spins drives and fans but never shows video): the spinning drives only prove the PSU is supplying basic power, not that the CPU or motherboard have successfully POSTed. was right to focus on POST failure; ’s follow ups show CMOS removal and reseating didn’t fix it, so here are targeted steps and checks that go beyond the suggestions already tried.

Practical next steps (rough order):

  • Visual inspection with power unplugged: look for bulging or leaking electrolytic capacitors, scorch marks, or damaged pins/traces around the front-USB header. Age-related cap failure produces exactly the intermittent-then-dead behavior described.
  • Bench the board outside the case: place on cardboard, connect only CPU+cooler, one known-good RAM stick in the recommended slot, PSU (24-pin + CPU 4/8-pin), a speaker and video. This rules out case shorts and bad front-panel wiring.
  • Use a POST speaker or cheap POST-code/debug card to read BIOS codes. No speaker = no clue; a code often points to RAM, GPU, or CPU problems.
  • Verify PSU rails and PWR_OK with a PSU tester or multimeter (+12V, +5V, +3.3V, and the PWR_OK/PG signal). A PSU can spin fans but still fail during POST.
  • Inspect the CPU socket and nearby pins/traces for bent pins, solder splashes, or corrosion—physical damage can stop POST even when fans spin.
  • If benching with a known-good PSU still gives no POST, the motherboard is the likely culprit; replacement or professional repair is the realistic next step.

If those steps are outside your comfort zone, document what you tried and the exact symptoms (LEDs, beeps, smells, intermittent behavior) and seek service or RMA. Always unplug mains before probing, use basic anti-static care, and avoid powering the board while making hardware changes.

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Member Avatar for SnowDog

If it used to beep and it doesn't now then it isn't POSTing.

Turn it off and unplug EVERYTHING. Leave it for a few minutes then plug the power cord in. Turn it on and see what happens.

If it won't POST it is broken and you need to find out in what way. No POST often means a motherboard fault. Your other symptoms before the total failure could point towards the MOBO and other things.

Is there any USB damage or did this just happen out of the blue?

What machine is it?

Member Avatar for Chaky

USB damage?

Member Avatar for SnowDog

USB damage can hold the whole machine down. We have had situations where engineers have been sent out with motherboards and it has been, for just one example (and there are others), the front USBs mangled.

We always check just to make sure.

Member Avatar for Chaky

I've damaged my PC's in a various numbers of ways (plugging the BIOS chip upside-down, plugging the video card half way in, etc), but never by an USB plug. I guess I'm not THAT clumsy.

Member Avatar for SnowDog

Had one the other day and the woman's daughter had mangled the front USB by trying to plug a firewire into it (I think it was an iPod).

Pins and front metal surround all bent, and machine having problems.

And don't get me started on when people plug mice, flash pens, or wi-fi adapters in the front, then either stand or lean on the cable.

Member Avatar for Chaky

If ti gets shorted.... I guess you can fry the mobo.

Member Avatar for doug91

ok so I just had the exact same problem. Reading this thread I have realized that there is USB damage. Someone was unplugging a USB cable rather violently (yanking it) and then the computer just shut off. How do I repair this USB damage?

Member Avatar for Chaky

If it doesn't boot any more, all you can do is unplug the USB jack directly from the motherboard. That way you will eliminate shorted USB to be the cause. If it still doesn't boot, then the damage is beyond USB. I say it is either mobo or PSU that is fried. Possibly both.

Repairing the USB jack is simple. Replace it.

Member Avatar for briansmall

When the power button is pressed the computer seems to be running fine. The power and activity lights both come on, the fans start and the hard drive and cd roms both start up. After that there is nothing, doesn't even come close to loading the OS. There is no beep and the floppy drive doesn't flash. The computer just seems to stall there for an eternity. The monitor doesn't show anything, just stays blank and receives no signal. Nothing internally was touched. It was working one night and the next morning it was goosed. It has booted very rarely, after countless attempts, but always shuts down randomly.

Is there anything worth trying or should it be launched into the nearest skip?

Cheers

What do you mean by nothing?
Does that mean the lights go back off?
And, that the drives and fans stop spinning?

If so, you might have a bad power switch. It happens all the time. To check it, you have to open the box and find where the switch (just the switch) connects to the motherboard. When you find this, you remove the connector from the mbd and momentarily short the contacts. If the system fires up, you have found your problem.

I've seen this several times. Of course it could be something else, but try the simple things first.

Alternatively you can "jab" at the switch randomly and possibly be able to determine that it is the problem.

Member Avatar for doug91

OK, so I disconnected the front USB ports from my Mobo. I also took out the CMOS battery. Still doesn't boot...
When I power on:
All fans spin
I hear the heard drive
I hear DVD drive
and the mobo light is green.

What else could be the problem?

Member Avatar for Chaky

If the drives spin, then it means that 5V is still being produced by the PSU. That would rule out PSU. My guess is that the mobo is dead.

In theory, any component can cause the no-boot. RAM, VGA, CPU...

All you can do now is reseat VGA and RAM and hope for the best.

Member Avatar for doug91

I reseated the VGA card and the RAM, but still the system starts up but will not POST. The fans spin on high power like they do at first start-up indefinitely. Could it really be the mobo. This think is less than 6 months old, and is a high quality ASUS board.
It did turn off right as someone yanked the USB cable out.. but there were no sparks or noise, the system just shut off. Now it won't power on at all.

Member Avatar for doug91

Also, if it shorted shouldn't there be burn marks somewhere?
I don't see any, but maybe I'm looking in the wrong place..
I

Member Avatar for Chaky

Use the warranty and do not mention the yanking.

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