Power Supply Woes

[KillerPotato]

I just received a new power supply today after previously thinking that my old one had gone down. I diagnosed the problem by using speedfan and found out that the 3.3v connector was only outputting 1.54v's. However, once I removed the motherboard connector on the old PSU, I saw that 4 of the connector pins were burnt and somewhat melted (the plastic part around them, that is), all belonging to the red wires from the connector. I simply ignored it thinking that it didnt matter because the power supply was bad anyway, but once I installed the new one and ran speedfan again, it had said that only 1.54 volts were still being output, yet the system ran fine.

Some other sources then told me that the mothreboard may be trying to draw too much power, and that it should be replaced. I thought that it would then be hot because the old one was somewhat melted, but after playing Half Life 2 for several hours and then shutting down the computer and then immediately removing the motherboard power connector, the connector was not hot at all. Can anyone tell me what is wrong, and what to do about it? Since replacing the old power supply, the computer has been completely stable, but I dont want the new PSU to go bad too just because of the motherboard.

Another problem is that I dont want to replace the motherboard now either, seeing as how nforce 4 boards are so close (which I was planning on upgrading to), and that after living for 6 days without my computer and still being at home (instead of being occupied on vacation or something), I couldnt bare to wait for another shipment from newegg and fedex. So can anyone offer advice? Maybe an alternate solution other than buying a new motherboard? Any help is appreciated.

The new one is a thermaltake 480W, while the old one is a turbolink 420W that came with my chieftech case.

 

[Harvey]

It sounds like something on your motherboard, or possibly a plugin board, is drawing way too much current from the 3.3 volt supply. A faulty component could do that without totally shorting out the supply. If so, instead of getting hot, as you expected, it would cause the power supply to limit the current to that output.

Try your supply on another motherboard. If it works, you won't be happy because something will need replacement, but at least, you'll have your answer.

 

[KillerPotato]

Except I dont have another motherboard to test it on

I dont quite understand what you mean with the power supply limiting the current to the output. Would that be a feature of this power supply, because the other psu obviously got a bit hot if the connectors melted.

Thanks for bringing the possibility that one of the plugin cards could also be drawing too much power. If thats the case, and I went out and bought a new mobo, that wouldve been kindof useless. I'll start replacing some of the cards and seeing if that makes a difference.

Thanks for your help so far. If anyone has any more suggestions/ideas, please share them.

 

[Harvey]

To avoid blowing up when shorted, most modern power supplie designs have circuitry to limit the maximum amount of current they will put out. The maximum allowed current may have been enough to get the connector hot, but unless the faulty component was a dead short, it would still put out some voltage (determined by the maximum current times actual resistance to ground), but not the full rated voltage.

If you have a friend who will allow you to do it, you can just unhook his power supply, and hook up yours to his system. It won't hurt his system, but if it works, you'll know your system is the problem.

 

[KillerPotato]

Taking out the PCI cards and replacing the video card didnt do a thing, so I guess the problem is in the motherboard. I'm going to try to find a way to test the power supplies on another system like you advised, but I probably wont be able to.

I was wondering, however, if anyone knew what kind of warranty Thermaltake has on their products, because if they have a good warranty, I could always run this power supply until it dies, which will hopefully be right around the time that nforce 4 boards are going retail. Of course it would be better if it didnt die at all, but I wouldnt even attempt to do this if they didnt have a decent warranty period.