Why did my motherboard catch fire? Also, what can be saved?

[c_hegge]

Re: Why did my motherboard catch fire? Also, what can be saved?

Who'se idea was it to make the USB and 1394 headers identical, even though getting it wrong blows the board up?

[ratdude747]

Re: Why did my motherboard catch fire? Also, what can be saved?

Who'se idea was it to make the USB and 1394 headers identical, even though getting it wrong blows the board up?

marketing.

[KeriJane]

Re: Why did my motherboard catch fire? Also, what can be saved?

Who'se idea was it to make the USB and 1394 headers identical, even though getting it wrong blows the board up?

Probably Intel, who also made the wonderful front panel HD audio connector physically identical yet electrically incompatible with the old AC97 connector...



All hail the mighty Intel....

Can we go back to PowerPC yet?

[shovenose]

Re: Why did my motherboard catch fire? Also, what can be saved?

Can we go back to PowerPC yet?

no because PowerPC is a proprietary slow piece of crap

[ratdude747]

Re: Why did my motherboard catch fire? Also, what can be saved?

Probably Intel, who also made the wonderful front panel HD audio connector physically identical yet electrically incompatible with the old AC97 connector...



All hail the mighty Intel....

Can we go back to PowerPC yet?

I guess I got lucky on the board you gave me... it had both... it also had both 3 usb headers and a 1394... at least they grouped them and color coded the headers.

my beef with intel regardign said baord (a dp35dp) is that they ditched one of the 2 IDE ports, the floppy port, and the ps/2 ports. the IDE i understand, since the controller chip is a single port marvell... but the rest perplexes me... at least they gave me 6 SATA ports (5 SATA+ one internal eSATA) and 12 usb 2.0 ports (6 internal headers, 6 external ports). I guess they were using Macintosh design concepts (ironic I put it in a mac clone case).

[zero10]

Re: Why did my motherboard catch fire? Also, what can be saved?

That's not the USB header!

Now it's pretty clear what happened - 12V to ground short.

The other pictures I could find of this board show that area has almost no components, so even cutting the whole area out, it would probably still work (maybe no more audio out.)

Your post had me panicked for a moment until I remembered there was nothing plugged into the front ports, not when it burned or at any time ever before, I never ever used them. The USB header doesn't connect anything to anything else unless a device is plugged in, so although I think you might be right and that cable is on the wrong header, it can't be a short caused by that. Or, in other words, I may be an idiot, but I think the failure is unrelated (I'm sure everybody says that....)

Looking closer at the picture (the computer is located out of my house right now for... smell... reasons so I can't physically look at it right now), it does appear whatever failed flared on the back first, then the front melted after. I think that might be important.

I have a new motherboard/cpu/ram on order and I will post an update with more pictures when I get this old board out and can take a proper look at it. New components should be here this week assuming NCIX isn't too backlogged with boxing day orders. I decided it wasn't worth throwing $80 in a new (unreturnable once tested) motherboard at this problem without knowing whether the other related (architecture-wise) components were any good. For an extra $160 I upgraded from my E6300 Core2Duo to an AMD Phenom II X6 1055T (2x1.86GHz --> 6x2.8GHz with better architecture) and from 2x2GB 800MHz ram to 2x4GB 1333MHz. This gives me the advantage of being able to switch the main OS over to Solaris and still run the linux stuff I need inside a virtual machine with acceptable performance.

Thanks for all the input , and the offers for instructions / suggestions on fixing the board , but as much as the tinkerer in me REALLY wants to dig in and try fixing the board I really think fixing it was never an option given the extent of the damage.

[zero10]

Re: Why did my motherboard catch fire? Also, what can be saved?

That's not the USB header!

Now it's pretty clear what happened - 12V to ground short.

The other pictures I could find of this board show that area has almost no components, so even cutting the whole area out, it would probably still work (maybe no more audio out.)

Oh dear, I just re-read the diagram you posted and I fear you might be right! Oh dear oh dear oh dear.... This just may be the dumbest mistake I have ever made with a computer. Quick, I need to get inside the internet and delete this entire thread before anybody can ever read it.

If I understand right, it is irrelevant whether anything was ever plugged into the port since the USB port would be grounded where it was attached, and that would indeed ground the +12V line on the firewire circuitry.

Firewire was disabled from within BIOS, but I doubt that actually powers down the firewire power circuitry.... that means it ran 850+ days with the firewire power shorted to ground, and it probably ran for ~250-300 days before that last reboot the same way too. If this is all correct, then I am now confused whether I should be happy that it ran so long like this, or furious that it didn't shutdown immediately when connected up this way...

[ratdude747]

Re: Why did my motherboard catch fire? Also, what can be saved?

either way, you will need to go on an expedition to ebay to hunt for a new board.

[Mad_Professor]

Re: Why did my motherboard catch fire? Also, what can be saved?

SO we can safely assume that this was user error, even tho ASUS is still a piece of shit.

My question is why did it short now and not then, when it was built and power on for the first time?

[ratdude747]

Re: Why did my motherboard catch fire? Also, what can be saved?

SO we can safely assume that this was user error, even tho ASUS is still a piece of shit.

My question is why did it short now and not then, when it was built and power on for the first time?

because it must have been a poor connection. either that, or it was a recent mistake.

[c_hegge]

Re: Why did my motherboard catch fire? Also, what can be saved?

If I understand right, it is irrelevant whether anything was ever plugged into the port since the USB port would be grounded where it was attached, and that would indeed ground the +12V line on the firewire circuitry.

Correct. The GND pins on the USB header connect to the case (which is grounded by the PSU, so plugging a USB header into the 1394 header would be like putting a wire between the +12 and the case (grounded). I think Ratdude747 has the only possible explanation as to why it didn't happen before.

[Junk Parts]

Re: Why did my motherboard catch fire? Also, what can be saved?

JP fears fire! Put that thing in the bin now!

[b700029]

Re: Why did my motherboard catch fire? Also, what can be saved?

SO we can safely assume that this was user error, even tho ASUS is still a piece of shit.

My question is why did it short now and not then, when it was built and power on for the first time?

I think it was always shorted, but the polyfuse limited the current so it just acted like a heater. The sustained heat eventually caused the fuse to fail by thermal runaway. According to the standard FW can provide up to 45W of power.

as much as the tinkerer in me REALLY wants to dig in and try fixing the board I really think fixing it was never an option given the extent of the damage.

You don't need to fix it, just cut that part out because there's no critical circuitry in that area and you don't need it

[tom66]

Re: Why did my motherboard catch fire? Also, what can be saved?

You're lucky it didn't burn the battery. Those are extremely flammable and might have done more damage.

[KeriJane]

Re: Why did my motherboard catch fire? Also, what can be saved?

no because PowerPC is a proprietary slow piece of crap

But the Mars Rovers and many satellites are PowerPC!
I'm pretty sure WALL-E might be PPC also.


If it's good enough for space vehicles shouldn't it be good enough for the rest of us?

[zero10]

Re: Why did my motherboard catch fire? Also, what can be saved?

I think it was always shorted, but the polyfuse limited the current so it just acted like a heater. The sustained heat eventually caused the fuse to fail by thermal runaway. According to the standard FW can provide up to 45W of power.

You don't need to fix it, just cut that part out because there's no critical circuitry in that area and you don't need it

I think you are right on the "why now?" bit, there have been no recent changes, heck, the case hadn't been opened in 852 days, and I doubt a poor connection, everything is clean in there and those connectors fit quite well. Can I really just cut that part of the board off? The system did power off before I got there so I think something else must have gone with it, but that would make one hell of a story if it can be saved, quite the battle scar.

[b700029]

Re: Why did my motherboard catch fire? Also, what can be saved?

Your PSU has short-circuit/overpower protection, so it would shut down.

Looking at intact pictures of your board it seems there's nothing there besides the header and probably the fuse above it, but better to scrub the area of soot and post a cleaner picture.

[toastygoodness]

Re: Why did my motherboard catch fire? Also, what can be saved?

But the Mars Rovers and many satellites are PowerPC!
I'm pretty sure WALL-E might be PPC also.


If it's good enough for space vehicles shouldn't it be good enough for the rest of us?

I liked powerpc as well. RISC architectures are more fun.

[Junk Parts]

Re: Why did my motherboard catch fire? Also, what can be saved?

WALL-E was clearly and advanced AI unit. Someplace on his body there had to be an " Intel Inside" sticker. He also could have been powered by AMD. Its hard to read WALL-E. What ever his systems were based on he did get the girl in the end.

[ratdude747]

Re: Why did my motherboard catch fire? Also, what can be saved?

But the Mars Rovers and many satellites are PowerPC!
I'm pretty sure WALL-E might be PPC also.


If it's good enough for space vehicles shouldn't it be good enough for the rest of us?

well, the hubble telescope is powered by an INTEL 486 DX.

most space probes use embedded type cpus... the 486 an386 were still inproduction until 2006 (386) and 2007 (486). why? embedded aerospace use. why? its what the designs call for and it is tried and true.

space probe cpus thus are oriented the same way as desktop cpus. there, where every milliamp matters, and reliablilty is a must, you pick the cpu that does the job, no less, no more.

likewise, probes using PPC were designed because thats what the designers felt was bust.... whatever the reason may have been.

Having had experience, freescale cpus (ppc based) are quite common in embedded applications... the biggest advantage tot he lower speed embedded models is low heat, low power usage, and programmablilty. for exaple, the NI cRIOs I were programming when I was on a robotics team were based on a 400mhz frescale cpu.