Mainboard Blown by Bad Shutdown

[enjay]

One of our PCs got turned off rather brutally today (i.e. mains power killed) and now it won't turn on again. Pressing the power button causes the Num/Caps/Scroll Lock lights to flash and the fans start spinning so the PSU would appear to be okay, but the PC doesn't even start the POST. Is there anything I can do for this beyond write it off and buy a new board?

[tech_guy]

Have you tried another known good HDD in it?

[strawberry]

try resetting the bios on it.

[enjay]

try resetting the bios on it.

Done that - well, I had it unplugged and held the power button in for a while, which resets the BIOS doesn't it, or does that just remove any residual charge from the board?

[strawberry]

I've never known to do it that way. theres usually a jumper on the mobo to do it, otherwise take out the system battery, disconnect power and leave it untill monday morning.

[kerrymoralee9280]

Have you tried another known good HDD in it?

Even without a HDD in it, it would reach POST.

[Michael]

You're describing the symptoms of a dead motherboard (by the sounds of things). Removing the motherboard battery will have little effect. The battery is there to save BIOS information and has nothing to do with any charge left on the board itself. To properly remove charge from the board, you need to disconnect the PSU.

@tech_guy - A computer can POST without a hard drive. You'll just receive an error no OS can be found.

[Heebeejeebee]

I've had a couple of these lately (crappy MSI boards). Only solution was to swap the mobo out.

HBJB

[SYNACK]

If you want a definitive answer as to what cooked itself you should get a POST tester card. It plugs into the PCI bus and reads the diagnostic signals of the busted motherboard and can tell you at what point post fails. http://www.pc-diagnostics.com/pc_dia..._pci_bus.shtml

This will definitively rule out the RAM or CPU.

[StewartKnight]

try another PSU, it could be the 12volt rail

I'd remove all components, except the CPU and start adding ram hdd etc to see if it posted.

[tech_guy]

We've had duff hdds stopping the successful completion of the post of some of our Dell PCs but that's Dell for you...

[K.C.Leblanc]

Sounds like a mobo failure to me. However I would try another PSU.

[EduTech]

Yup i agree from what ur sayin sounds like a mobo Failure.. replace the motherboard should be oki.. i have had systems that dnt POST change the board everythings sound

but on the other hand.. like a few other people are saying its not always the mobo that causes the sytem not to POST.. i would say the best way round it is to do what StewartKinight was saying

Hope u get it sorted
regards

James

[Oops_my_bad]

Im not sure the power loss would have blown it, more likely to be when the power came back up again

[mrtechsystems]

Basic check on a motherboard you normally get a green light to say there is power to the board