This is my first topic here. I register here because i have a problem.
Ihope that my "not so good" english (i'm belgian) won't be a problem.
At first, my config:
Mb: Asus a7n8x-x
Cpu: amd athlon xp 3000+
Graphic card: ATI radeon 9200SE (with a direct connection to the power supply, the same connector as an hard drive)
RAM: 1x512 ddr (i don't remember the brand)
sound card: soundblaster live 5.1 digital
2 hdd (master & slave ok)
Monitor: philips 107s
1 dvd reader
1 dvd writer
1 ethernet 10/100Mb Dlink
ps 1: SHS 400w (lived 16 mois)
ps 2: lpe2 400w (liver 1 week)
ps 3: lpe2 400w (liver 20 minuts!!!!) both lpe2 bought in the same shop
At the begining, i used my computer for 16 month without any problem. One day, the computer shut down (as if i took back the cable). Later, i changed the power supply for an lpe2 400w who lived 1 week. I changed again for tha same model. It lived 20 minute.
As i don't really know about power supply and what could make them
burnt. (i have never seen smoke or even smell burn from my computer or the power supply), i would like to learn what can "broke" a power supply.
I tried to be clear and not to do too much mistake.
When PSUs die like that, it usually means one of these things:
1 - The motherboard is damaged (i.e. short-circuit on the motherboard) or something else connected to the PSU is pulling too much current.
I would look on the motherboard and the graphics card for damaged capacitors. Leaked capacitors are too common (so much that there is an entry on the wikipedia called Capacitor plage) on some-years-old mobos and a common cause of this kind of problems ("failing capacitors can fail such as to form a short circuit, or with a very high leakage current").
2 - Big power spikes on the power line (but that would affected other things too, like light bulbs that would not last long...)
If it's so, I would try using some kind of surge protection product, like the ones APC (APC Belgium ) has (or an UPS if you can afford for it).
3 - Very bad luck.
On this case you should.... get some good luck charms
I agree with Neopolus. Either there is a short in your system that is overheating the power supplies, or you have a problem with surges over the incoming power lines. The power line surges are probably the easiest to answer, as electric light bulbs, radio, TV and other electrical stuff would start acting weird, blowing out suddenly and all.
Most likely the problem is in your computer. First you can look for obvious problems, capacitators leaking, wires burned, or other marks that don't look normal. After that, the best thing might be to take it to a shop and have them test the system. That will cost a some money, but its better than trying to test components blindly.
If you have problems with powerspikes or a closed loop on ground (the black wires) inside the computer then you would kill which ever power supply you try to install regardless of how many watts it is rated at, actually you can easily toast your whole system. Your system should be able to run with a good 300Watt power supply.
I know of people running a Dell Dimension 4500 with the original 250Watt power supply with this configuration:
1GB of ram
NEC DVD RW 16X
Memorex 52X CD RW
80GB HDD 1
250GB HDD 2
Sound Blaster Audigy2.
Above configuration use at least as much power as your system.
The original Dell 250Watt PSU would normally be marked as a 300Watt if a quality brand or 350-400Watt if a cheap brand.
I was asking my self: If it was something inside my computer who make my supplies dying, a 500w would burn too or it could be ok?
If it's a dead short, it would most likely take a 500 watt PS down too. What bugs me is that you didn't smell anything on the last PS that went in just 20 minutes. Typically, if a short is involved in killing a PS, the high current flow gets a resistor, a cap or something in the path hot enough to generate significant odor. So if your last PS had survived a week or so, it is easily conceivable that were out of the room when it burned up. But I'm assuming that you were around much or all of the 20 minutes when the last one died?
"or a closed loop on ground (the black wires) inside the computer" what do you mean by that? i didn't understand those words
I just think about that: i have facial usb port on my "tower" that i didn't plugged. Those cables are tied but maybe the connectors touch the metal parts of the tower. Are talking about that kind of things?
For each i was there. I was using the computer and it shut down as if i had unplugged the main electric cable. No smells, no smoke.. nothing. But the power supply had no more response. As soon as a new one had been plugged, the computer start back as if nothing happened.
I just opened my computer (once again) and for me everything is ok: no black spot, nothing burnt, nothing special to me... Thats the tird power supply i killed, and my computer is still working without problems (except from the power supplies...)