Motherboard fire

[Morgwolff]

Recently I tried to build a new computer but I could not get it to power up (not even the fans). I tried a different power supply but it still did not work.

After reading some forums on the Internet I believe I found the problem. I had left some extra brass standoffs in the case under the motherboard (improper grounding).

I removed the extra brass standoffs and the next time I started the computer it started to boot up. Unfortunately, the top left part of the mobo caught fire a few seconds later. I know that the improper grounding caused by the extra brass standoffs can ruin a mobo but none of the threads that I read mentioned anything about potential fires.

Did the initial attempts to power the computer (with the extra brass standoffs in) damage the mobo in a way that it would start a fire if it were powered normally? Or is there some other separate reason for the fire?

Specs:
CPU INTEL|C2Q Q6600 2.40G 775 8M R
DVD_BURN SAMSUNG|SH-S182M/BEBM BK %
MEM 1Gx2|G.SK F2-6400CL5D-2GBNQ R
MB ASUS P5K P35 775 R
HD 400G|ST 7K 8M SATA2 ST3400833AS
VGA EVGA 640-P2-N821-AR 8800GTS R
PSU CORSAIR|CMPSU-620HX RT

Thank you for your time and sorry for the long post.

 

[mechBgon]

If the power supply detects a full short-circuit condition, it would probably refuse to start at all, which explains your first set of symptoms.

Once the improper grounding had been fixed, if you had your ATX12V cable confused with the 4-pin section of your 24-pin ATX2.0 cable, then you might have a fire when the power supply tried to start. The plug on those two cables could fit in eachothers' sockets, but they have different voltages, so it's important not to mix them up and plug them into the incorrect receptacles.

ATX12V cables only have black and yellow wires, no red or orange ones. For your motherboard, it belongs in the "8-pin CPU power connector" in this pic :camera:.

The 4-pin part of the 24-pin ATX2.0 cable has one each of yellow, black, red and orange wires, and belongs in the receptacle marked "24-pin ATX power connector" along with the other 20 pins.

Also, welcome to the Forums

 

[wjal]

A common source of motherboard fires is cross-connected onboard USB pins.

 

[montag451]

I never heard of fire from USB incorrectly slotted - it is possible i wrote off a mobo by doing this, but there were no fireworks.

Was there a bang? or a fizzle? or a whimper? before you noticed flames.

 

[btcomm1]

What? wjal are you saying that if you hook up the USB pins incorrect that connect to the front of the case it could light your motherboard on fire?

 

[Morgwolff]

I believe there was a popping noise and a small spark that shot out when the fire first started. Thank you everyone that has replied so far.

 

[montag451]

The only time I had smoke/flame from a computer was when I trapped a case LED cable against another, shut the case, hence shorting out the wires - lots of smoke, hint of flame, a little panic, and no LED anymore, although I'm sure it would have worked if it was rewired - I cut the cables for safety.

So, did you somehow short out any cables?

 

[Morgwolff]

I installed a new Mobo and made sure not to make any of the mistakes mentioned in this thread. Everything seems to be working fine now. Thanks for the help everyone.

 

[mechBgon]

That's good news Enjoy your new system!

 

[RadiclDreamer]

Originally posted by: montag451
I never heard of fire from USB incorrectly slotted - it is possible i wrote off a mobo by doing this, but there were no fireworks.

Was there a bang? or a fizzle? or a whimper? before you noticed flames.

I have, it happens more than you think

 

[montag451]

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