can a bad cpu kill a power supply?

[ibsleepn]

I was building an Intel system for a friend (my first intel build) and had everything working for a few days. Shut it down and came back to it later and it would not boot. Cpu fans and case fans spun but nothing else. No post codes at all. Even removed the memory and video to try to generate a post code. Swapped ps with the one in my amd system (an enermax 480) and same thing. The ps (JGE 450) in the intel was a 20 pin and I was using a 20 to 24 pin adapter. I plugged the ps from the intel into my amd system and it posted just fine. So i thought the Intel board was bad. I replaced my ps back into my amd system and no joy. Could hear a click from my speakers when i pushed the power button but that was it. Got a ps tester and it showed that it was bad (can't remeber now what it was). Plugged the ps from the intel build into my amd amd same thing no boot no fans no nothing. I plugged it into the tester before i plugged it into my mb and it showed good. Plugged in back into the tester and I heard a snap and nothing showed on the tester. Since the ps was out of warrenty i took the cover off and saw that the 6.5 amp fuse blew. Bought an antec 485 watt ps and hooked it up to my amd board and same thing nothing. Plugged in the tester and it showed that there was not a -5v signal. With the antec the system at least spun the fans for about 1 sec when i push the power button but nothing else. Replaced that with and enermax 500 and a new gigabyte MB with the same cpu and memory and same rusults. showed no -5v.

Now after all this.. after i had removed my original enermax 480 and put it back into my system, could whatever damaged the intel board damage my enermax480 and then the enermax damage my cpu and then my cpu damage all the other ps that i have tried?

Intel build
msi p4n sli
pentium d 830
1 gig corsair value ddr2
msi 7800
jge 450 watt ps
lite on dvd-rom
liteon dvd-rw
maxtor MaxlineIII 250 sata
floppy

My amd system
Asus sli board
amd 3500
2 gig ddr
1 ide 120
2 sata 80 in raid 0
2 sata 250
evga 7800gt
enermax 480 watt ps

[EXreaction]

Welcome to techIMO.

I guess it probably is possible...but highly unlikely...replace the fuse in enermax, and try it in your amd system again...

Next time you try the Intel system try oly plugging in the mobo, cpu, 1 stick of ram, and your graphics card if you don't have integrated...your dvd drives, or harddrive could have a short...

[ibsleepn]

thanks for the reply.

it was the jge ps that blew the fuse. I misread the fuse and replaced it with one with to high of amps and blew the ps when i plugged it into the tester. Made some nice firecracker sounds. Bad mistake on my part. BTW it is not the tester, bought another brand tester and have recieved the same reslults with other ps. The enermax 480 wouldn't power on. Can't rember what the tester said was wrong with it and i no longer have it.

Ib

[ibsleepn]

new problem i think. Just got a replacement ps, plugged it into the tester and it showed no -5v. Didn't even plug it into anything but the tester. I am showing 123 volts at the outlet but i don't think that could cause a problem.

???

[DanU]

Newer ATX power supplies have dropped the -5V supply. It's no longer needed in modern computers.

Power supply testers have a very limited usefulness. They only draw about 25W. This is nowhere near what an actual computer draws. It's an almost meaningless test.

Why oh WHY did you even attempt to use a cheap 20-pin power supply with a dual-core Pentium D computer and a GF 7800 ???? If all you've blown is the fuse, then consider yourself very lucky.

Get a proper 24-pin, dual +12V rail PSU with at least 400W and from a reputable manufacturer. Power supplies (if they're built RIGHT) are self-protecting. If they can't handle the load, or if someting is shorting out, then they will shut themselves down to prevent damage.

There might be a short somewhere between the motherboard and case. Try removing the motherboard and using only the CPU, CPU Heatsink, PSU, memory, and video card, try booting up. You should at least POST.

[ibsleepn]

Originally Posted by DanU

Newer ATX power supplies have dropped the -5V supply. It's no longer needed in modern computers.

Thank You!!! did not know about that. Just checked the ps and the jge did have a -5 lead in the 20 pin but the new enermax 500 did not have -5v lead in the 24 pin connector. Guess that means the cpu is bad cause i tested the cpu, memory and video on a new gigabyte board with a new ps and it did not post. If the memory or video was bad it would at least post. I would think anyways.