Smoke From Computer

[lampshade]

Was starting off my thanksgiving break with playing some Skyrim... then all of a sudden i heard the sound that windows makes when something is detached from the computer and it booted off. I look over and smoke is coming from my top case fan. I opened up the case saw no marks of fire and tried to boot it back up. The motherboard lights up, all the fans are spinning, and cpu fan is spinning, but no display. I've never had an issue like this and was wondering if anyone had any ideas of what it would be.

Specs:
Case:Coolermaster Storm Scout
Motherboard: Asus Crosshair Formula IV
CPU: AMD Phenom II 1090T
RAM: GSKILL 4Gb 1600CL9D
Video: XFX 6870
PSU: XION 850W

EDIT:

Found the burn on the motherboard on the third pcie slot and above it. What do you think could have caused this?

 

[clutchc]

My guess is the graphics card fried itself.

 

[lampshade]

Well, at first I agreed with that, but when I finally saw the burn marks it was below the 3rd pcie slot (unused) and on it and around it. So... I was courious if anyone would have any ideas of what could be the cause.

 

[manu 11]

your psu, xion???

 

[diellur]

I'd be inclined to think it was the PSU, if an unused slot cooked.

 

[p4nz3rm4d]

I think is was the psu that fried a few capacitors around ur pci...

 

[manu 11]

get a new psu, i think it fried itself or fried other parts.

 

[clutchc]

Can you send a pic of the burn? Is it near a capacitor? You say the burn is on the motherboard itself. Is it on a trace, or on a component? I'm leery of it being the PSU.

 

[lampshade]

 

[hunter315]

Looks like a capacitor blew on the motherboard, that at least explains the smoke. As for the root cause of failure thats harder to determine, but i would assume for now that the motherboard is dead. Also, how old is your PSU? It may have been the source of the issue, or your motherboard may have just had a damaged capacitor that died in a catastrophic component failure.

 

[lampshade]

Both the motherboard and the PSU are about a year and half old.

 

[clutchc]

Ah yes, the first few fingers/contacts in that small section of the PCIe x16 slot contain the +12V power. It appears that either some electrically conductive foreign object made its way into the slot and short circuited the contact fingers, or the contact fingers themselves came lose and shorted. You might check the backside of the board to see if something made contact with the solder traces under the slot.

Either way, I don't see much use keeping the board. Even if it manages to work somewhat, it will always be a fire hazard that you would not want to leave un-attended.

 

[lampshade]

Well I'm hoping I'll be able to RMA the board because it is still under warranty, so I have no plan on keeping it, but like others have expressed, I was a little worried that this could have been a PSU issue because it was a budget buy. Would it be a good idea to pick up a new PSU before I get a new motherboard, or do you think this was just an unfortunate event with little relation to the PSU?

Also, nothing looked out of place on the backside of the board- except for the burn that made its way through a little.

 

[clutchc]

The reason I was curious about theback side of the board, was in case something was shorting it from behind... like an extra unused standoff.

I can't imagine how the power supply could cause that. There is no electronic component in the slot that could have had a voltage surge. The slot is nothing more than a bunch of open contacts waiting for a device to be inserted. With nothing in the slot, there is no load. Although... I can't tell for sure if those are tiny diodes just above the slot or not. On second glance, it almost looks like there may be diodes in that location. If those are indeed diodes, one of them could have failed. But it looks more like the arc occurred inside the slot.

That's not to say that the short circuit may not have damged the PSU if it is an inexpensive unit, though. On a quality unit, it should have short circuit protection for itself.

If you feel the PSU is a low quality unit, it would probably be wise to get a better one any way...

 

[lampshade]

According to the PSU specs it does have Short Circuit Output Protection. Thanks for the information and the replies.

 

[lampshade]

Best answer selected by lampshade.