Topic: Sniffing the box
started by: Hellraiser
Posted by Hellraiser on Feb. 18 2002,23:32
I was calmly browsing the internet this afternoon, when all of a sudden, my computer died. The power for the computer just went poof, even though my light was on, the monitor light was on, the stereo lights were on, the computer just completely shut down. I then caught a whiff of electrical burn smell, and I feared the worst.So What I did was take the case off and sniff around inside. Sure enough, the smell was strongest from the power supply box (300 W), and the box itself was about 50 degrees hotter than anything else in the case, too hot even to touch.
I went ahead and bought a new box, hoping that nothing else in the case was fried, and about 5 minutes after getting home, my computer was back up and running.
Out of curiosity, I took apart the old power supply, and guess what I found: about 40 or 50 drops and strings of melted plastic, some on components, and some on the inside of the case, and some dangling from the wires!!!!
The closest thing I can determine is that it was melted today, since it had no dust on it, but lots of dust in it and between it and the components. I'm not sure if the plastic was the cause of the short-circuit or one of its effects, though I happen to think it was the cause, since it was dripped down inside several of the copper wire coils, and running between the connectors on several of the transistors. I'm not sure what the plastic was originally, though by the color, my guess is that it was a couple of the little wire-ties they use, though it would have had to be 3 or 4 to get that much dribble.
I'm planning on testing all the components in it in my little electronics workshop downstairs, and see if any of them are defunct, so I can find out why the whole thing just shut down like that. Who knows? I may get it running again, in which case I'll have a spare power supply box, and those bitches ain't cheap. Cost me $50 to get a new one because only one place in the area had any in stock.
Anyways, maybe any of you who've had computer heart-attack scenarios can share your stories below. Or not....
/end of my geek moment of the day
Posted by Spydir on Feb. 19 2002,00:08
that happened to one of my old computers, but luckily I had a better ps within 3 feet I could swap out in a computer I rarely ever used
Posted by Wolfguard on Feb. 19 2002,01:34
What you smelled was the magic smoke that resides in all electrical equipment. Once this smoke is released the part stops working.From your discription it sounds like a cap burned through and shorted. this makes them pop and spill their guts. can be quite exciting if its a big one.
This is not the cause of the failure. What you most likely are looking for is a bad rectifire (ac-dc converter) or a blown power transistor. one will pass ac to the dc parts and make them pop and the blown power transistor will cause a dead short.
Have fun.
Posted by Hellraiser on Feb. 19 2002,03:48
| Quote (Wolfguard @ 18 Feb. 2002,20:34) |
| What you smelled was the magic smoke that resides in all electrical equipment. Once this smoke is released the part stops working. |
Hehe
Still no luck in determining the defunct component, though I've determined that the goup is not in fact plastic... it has roughly the consistency of glue from a glue-gun, and is way too soft for melted wire-tie. Thus it cannot be from that. I can't figure out what its from though.
Posted by caseman984 on Feb. 19 2002,04:35
At least your smoke wasn't visable. When my friend and I were building the box I'm working on now, we had some trouble getteing the internal speaker working. Motherboards and Cases just don't like to et along sometimes. So, we turned around the connector for the speaker to the motherboard, unusre of which was negative and positive (stupid, I know, but it wasn't my box at the time). The system booted but froze at POST. We turned around and were discussing this amongst ourselves when we smelled something. We looked at the box and white smoke was billowing out of the back of the case. Quite possibly one of the most frightening sights I've ever seen. I jumped down and unplugged the whole damn thing from the wall, quickly opend the case, and opened a window (by this time It had filled almost half the room).The wires for the internal speaker had melted away, and onto the case in places. To this day I do not know what happened there. We took apart the power supply, and there was no visable sign of damage, but it did not work. I happened to have a 300w sitting around(don't ask), so we put that in there, disconnected the speaker, and it booted fine.Weird crazy stuff.
On another note, I didn't realize just how inflated the prices were for powersupplies. They don't cost that much to build, parts-wise, but they are damnned expensive buggers.
Posted by BlackFlag on Feb. 19 2002,11:53
See my topic in the rants forum called "crash and burn"
Posted by ASCIIMan on Feb. 20 2002,01:59
I'll have to agree with Wolfguard on the capacitor mini-explosion... That was the pretty much the first thing that came to mind.