PSU issues and burnt atx connector

[PickledSheep]

Recently my computer has been very unstable. It would randomly reboot
in windows, or even in the bios or during post. I had felt it was
possible overheating. It has recently gotten much worse, today to the
point where it would no longer post. I immediately began to remove
the motherboard to make sure the heatsink was properly seated on the
cpu. While removing the 20 pin ATX cable from the motherboard i
noticed four of the connectors (all red cables) were burnt
and slightly melted along with the connector on the motherboard side. I removed the psu
from the case, and also noticed a strange melted sort of substance
through the fan opening.

I put the psu out of my parents computer (generic 350W PSU, 15A on 3.3V, 25A on 5V and 13A on 12V) in my computer, hooked it back up (except for the CD drives, also i clocked it to the stock voltage) and powered up. It seemed to work fine. Within 5 minutes it produced a nasty electrical smell, and some melted guck appeared inside. I'm not sure if this melted guck is some sort of adhesive, or something similar i am unaware of. It is a milky whiteish yellow, and it has appeared at the bottom of a large capacitor and all over the inside of the SmartBlue.

My question is, did my computer just crush both of these power supplies, and i just need to buy a better one (considering a neopower, modstream or powerstream). Or is there actually something wrong with a piece of my hardware, that is causing the PSU's to overvolt? Also what caused the burnt atx connectors? I fear that replacing just the PSU will not solve the problem, and the the mobo or something else may be the issue. Any suggestions?

Computer specs:
AMD Athlon XP 2500+ (overclocked to 3200+ at stock voltage)
ASUS A7N8X Deluxe Motherboard
512MB Corsair XMS RAM
ATI Radeon 9800 Pro
2X80GB Western Digital HardDrive
BenQ DW1620 DVD Burner
BenQ CD Burner

 

[larrymoencurly]

Manufacturers use glue to hold components in place, like capacitors and coils. Antec's is opaque yellow, and in my experience it turns brown and hard instead of melts. Other companies use silicone rubber (glossy white or clear -- Antec uses this in addition to the yellow stuff), which can withstand 250C indefinitely, some others use hot glue (semi-glossy clear), which will melt at high temps, or something that looks like thick semi-gloss white paint (Enermax, Delta).

Capacitors also ooze their own stuff, but it's usually a brown color and can leak out the tops as well as the bottoms. If you see any stuff on top that isn't glue, or the capacitor is bulging on top, then that capacitor definitely has to be replaced, and probably so do all the others of the same brand and type.

When overloaded, PSUs are supposed to shut down before any damage occurs to them, and Antecs seem to do this well, but many other brands don't. Are you sure that the smell is originating from inside the PSU and not at the mobo power connector? The connector can make two different smells, one from the white nylon, another from the vinyl insulation on the wires.

If the computer shut down with two different PSUs, I would suspect the mobo, probably its own electrolytic capacitors in the voltage regulator section -- see www.badcaps.net

 

[PickledSheep]

Ok, i have been running this system for over a year with an Antec SmartBlue 350.
As for the second power supply, i didnt wreck it, i just smelt electrical so it was obviously overeheating so i powered down immediatley. I'm thinking this psu just couldnt handle my computer. This psu still works fine in another computer. It sounds like this "guck" im seeing inside the psu may in fact be adhesive, and in antec psu's this adhesive supposedlys browns, which is what im seeing through the fan hole. It doesnt look like the stuff leaking out of the caps on [L=BadCaps]http://www.badcaps.net/[/L]. Also these problems have arisen recently when i put in my new benq cd-rw and dvd-rw drives.

So i guess im kind of lost. Should i try and warranty this 350 watt smartblue (or will a replacement just have the same problems), just order a new psu, or replace the motherboard as well.