Question Burning smell from motherboard

[MuPro]

OK. I did some research and found out that it is OK to use rubbing alcohol (70℅ isopropyl) to clean motherboard. Mine was really dirt so I took all the hardware out and cleaned it with isopropyl alcohol, left it to dry for some time (1 hour). I also cleaned my GPU and RAM with it. So I turned the buttons on and the PC automatically started had no display and under 3 seconds I smelt a burning smell I immediately shut my PC down. Now that I have left it alone for a while the PC turns on and gives 5 long beeps (motherboard failure) I smelt the RAM, nothing wrong with it. So what should I do?

Specs: HP Compaq PC with AMD 8600b triple core processor 2.3GHZ

 

[MuPro]

No signs of burns though

 

[ElectrO_90]

Something has gone bad, as you smelt it.
Are you sure its mobo and not PSU?
The thing you need to do, is smell your computer closer and find it.
It's probably something to do with the power on the motherboard, near the CPU - all the rectifiers there.

 

[MuPro]

Something has gone bad, as you smelt it.
Are you sure its mobo and not PSU?
The thing you need to do, is smell your computer closer and find it.
It's probably something to do with the power on the motherboard, near the CPU - all the rectifiers there.

The smell sure is strong between Mobo and PSU it could be any of the two, the system powers up well though (I.e All fans work)

 

[ElectrO_90]

You need to remove it, and find out the problem.

 

[drea.drechsler]

Do you know what motherboard or system model number precisely?

I'd also check in the area of the power connections and all sockets, including the CPU socket. Look for contamination in socket contacts..like bits of dust or lint that might have been soaked with alcohol, didn't have a chance to dry out and then charred into carbon to provide a high-resistance short between contacts.

Be sure to check BOTH sides of the connection including edge connectors on GPU or other cards.

 

[MuPro]

The PSU?

 

[MuPro]

Its HP Compaq dc5850 I will check the carbon

 

[drea.drechsler]

Its a dc6850. I will check the carbon

You'll have to check closely...get a bright light and a powerful magnifier if you have one. If not take some good quality pictures with camera that does macro mode and look at them.

 

[MuPro]

Do you know what motherboard or system model number precisely?

I'd also check in the area of the power connections and all sockets, including the CPU socket. Look for contamination in socket contacts..like bits of dust or lint that might have been soaked with alcohol, didn't have a chance to dry out and then charred into carbon to provide a high-resistance short between contacts.

Be sure to check BOTH sides of the connection including edge connectors on GPU or other cards.

I found the alcohol soaked dust area (its brown, if it was burnt wouldn't it be black) that is the place where the smell is strongest. Its around a chip

 

[SkyNetRising]

Sounds like - it's time for new motherboard.

 

[MuPro]

The smell is a mixture of water and burnt electronics

 

[MuPro]

Sounds like - it's time for new motherboard.

I don't think I can replace a motherboard on a branded PC. I'm so screwed

 

[SkyNetRising]

Yes, you're right. That's pretty non-standard board.
May be you can find replacement on ebay.

 

[MuPro]

THE PROBLEM IS NOT SOLVED I'm sorry im new

 

[drea.drechsler]

THE PROBLEM IS NOT SOLVED I'm sorry im new

No it's not yet...but don't give up on it yet either.

As I said, if it's a carbonized bit of stuff it might be causing a high resistance short which is what's making if fail POST and issue the 'motherboard failed' beeps. SO...you could try cleaning that area.

I know, you'll cringe...with alcohol and a brush, a soft-bristle tooth brush should be fine.

After you have it clean and no traces of black or brownish material left then dry it thoroughly this time. Let it air dry for AT LEAST a day...maybe a couple. If you've a hair dryer use that on it too. Parts are generally safe to hair dryer temperature if unpowered... in fact, during solder reflow process preheating is quite a bit hotter and parts have to endure that, with margin.

 

[MuPro]

i will try and report

 

[MuPro]

No it's not yet...but don't give up on it yet either.

As I said, if it's a carbonized bit of stuff it might be causing a high resistance short which is what's making if fail POST and issue the 'motherboard failed' beeps. SO...you could try cleaning that area.

I know, you'll cringe...with alcohol and a brush, a soft-bristle tooth brush should be fine.

After you have it clean and no traces of black or brownish material left then dry it thoroughly this time. Let it air dry for AT LEAST a day...maybe a couple. If you've a hair dryer use that on it too. Parts are generally safe to hair dryer temperature if unpowered... in fact, during solder reflow process preheating is quite a bit hotter and parts have to endure that, with margin.

So i cleaned it with rubbing alcohol and a tooth brush. Just a few traces of brown is left, which i can't seem to remove.

 

[Rogue Leader]

FYI thats a BTX style motherboard which are no longer made. If you can't fix this you'd need to find the identical board on eBay, not really worth it.

Also I'd bet the dust covered component is the thing emitting the smell, no amount of cleaning will fix that burnt component. Depending what it is you MAY be able to soldier and replace it, but many Motherboard soldier joints are VERY tiny, so you may have a hard time with that without a real soldiering station.

 

[mortemas]

Can you take pics and show us what this looks like? Use compressed air or a hair dryer and thoroughly blow out every nook and cranny, then leave it in a warm, dry place overnight (or outside if it is warm, dry and sunny where you are right now. You didn't give it nearly enough time to dry.

 

[alceryes]

Question.
How did you 'clean it with isopropyl alcohol'? Did you use q-tips dipped in alcohol or pour alcohol onto the motherboard?

 

[drea.drechsler]

Can you take pics and show us what this looks like? ...

At this point, some pictures would be very helpful. If there are carbon tracks embedded in the board surface (for instance) it may still present a high-resistance short that prevents the board from operating.

That of course assumes it's still salvageable as the short could have damaged a voltage regulator which prevents it from powering that chip. That's still a real possibility.

 

[MuPro]

Question.
How did you 'clean it with isopropyl alcohol'? Did you use q-tips dipped in alcohol or pour alcohol onto the motherboard?

Alcohol pads

 

[drea.drechsler]

Alcohol pads

Next time, I hope you just blow the dust bunnies out with 'canned air'.

https://www.amazon.com/Compressed-Air-Dusters/b?node=3012916011

 

[RememberThe5th]

I would not use below acetone or isopropyl (90%).
Ive washed my mobo in jar 5 times tho.

 

[MuPro]

At this point, some pictures would be very helpful. If there are carbon tracks embedded in the board surface (for instance) it may still present a high-resistance short that prevents the board from operating.

That of course assumes it's still salvageable as the short could have damaged a voltage regulator which prevents it from powering that chip. That's still a real possibility.

https://imgur.com/kWZZHab

this is whre the smell is strongest, it was far more dusty so i had it cleaned with the brush, but the PC gives the same error and the smell starts when i turn it on. (Left it to dry for a day)