Computer rebuild problems - need advice

[jpoley]

HELP!

I have a home built computer which had problems for a while then died. It had an ASUS P5B-E MB, Kingston RAM, and a Core Duo procssesor. The funny issues it had up to death included not turnning on or failing to boot past the BIOS screen. I have a power supply tester and the PS tested good. I swapped the RAM for a pair of Crucial chips and that made no difference. I was able to turn it off for a while and it would turn on later or, sometimes if I unplugged it and then plugged it back in, it would function as normal until turned off again. Finally it just stoped turning on at all. No power supply or CPU fan activity. Tested PS and it still looks good (fan does turn on when tester is attached)

Is have purchase a new Gigabyte MB & power supply. I swapped those into the box, moving the old CPU and memory. Turned it on and again no fan activity (only the power leads attached and the CPU, RAM & heatsink in place).

I figured with the new MB, the problem must be the old CPU. So, I purchased a new CPU and replaced the old one. Still have the same issue.

Please tell me I am doing something stupid and do not need to purchase more parts. Not sure what to try next or how to determine which part is really bad or maybe if I received a DOA MB or CPU.

JDP

 

[ohiou_grad_06]

Are you sure the PSU is good? Just because it tests good does not mean a PSU is good. You've tried the obvious things, I don't think I've seen a cpu fry, I would try another PSU myself. See if a friend has a spare you can try. Btw, if it's socket 939, I would not dump anymore money into that system. At what you are probably paying, should have just gone up to the AM2 socket.

 

[jpoley]

Yes, swaped the PS at the same time as the MB. Both tested good but I swaped it anyway like you suggest.

I was not very clear. The sequence went like this...

problems
massage MB - starts working
problems again quickly after (maybe a week)
massage MB again - still problems
swap RAM - starts working
problems then dead after working for a month
swap MB & PS
dead as described above

The other thing that was suggested to me is to check if the MB is shorted to the case. How can I check this? I have a DMM but where do I put the lead on the MB??

 

[jpoley]

Yes, swaped the PS at the same time as the MB. Both tested good but I swaped it anyway like you suggest.

I was not very clear. The sequence went like this...

problems
massage MB - starts working
problems again quickly after (maybe a week)
massage MB again - still problems
swap RAM - starts working
problems then dead after working for a month
swap MB & PS
dead as described above

The other thing that was suggested to me is to check if the MB is shorted to the case. How can I check this? I have a DMM but where do I put the lead on the MB??

 

[jpoley]

Great hit the back button and double posted... what a newbie. If I flame myself, is that like talking to myself?

And thanks for the reply ohiou.

 

[ohiou_grad_06]

Hmm...you may have just gotten a couple of flaky boards dude. I don't ever remember having that happen to me yet, and I'm a computer tech by trade. So what brand of PSU are you using? Maybe if you are using a cheap PSU it's killing parts because it's not very stable even though working?

What are the amperage ratings on the PSU and what are you running off of it?

 

[jpoley]

First of all, I spent some time searching the forums here reading, reading links, etc. I must say that You guys have a great community with some great info... my thanks. I have been working on/building computers since 1983 ( MUCH less today than my ResNet days for sure ) but never had this kind of trouble... wait I take that back. Anyone remember Parkard Bell computers?!

Anyway, tested the hell out of the two PS (I had fun dusting off and playing with my volt meter) one PS is a brand new Thermaltake 500W. The other a two year old RaidMax RX-500.

Results for RaidMax:
Wire color - Result
orange 3.4V
yellow 12.16V
red 5.11V
blue -11.44V
white -4.72V
purple 4.77V

grey 5.09V in about 1 sec

Results for Thermaltake:
Wire color - spec - reading
orange 3.39V
yellow 11.90V
red 5.12V
blue 10.26V
white no wire
purple 5.06V

grey 5.1V in about 1 sec

I don't know if that helps really but they look okay to me.

I then tried both CPUs in both MB on both PS... No response?!

So, can someone confirm that the PS & CPU fans should turn on with just a PS, MB, and CPU attached? Even without memory right? I read that I would hear a couple of beeps if the RAM was not installed and a speaker was attached without the memory but the fans will power up, right?

Cheers,

JDP

 

[ohiou_grad_06]

Might be ok, but what are the amperages listed on the sides for the 12v+ rail? Like mine for example is 24 amps, some are 18, 20 etc. Sorry for making you work harder, lol. But sometimes folks get power supplies with high wattage, but they really don't have the amperage to carry what your doing. I think on a rig of mine, it did do some sort of series of beeps when it couldn't pick up my memory, whenever I reseated the memory, it worked fine. If you do some searching on google, you should be able to find what those beep codes mean and hopefully that will lead you to your problem.

Also, when you installed the boards you did use the standoffs I'm assuming?

Btw, yes I do remember packard bell, my first computer was a commodore 64 at age 5 if anyone remembers those....

 

[jpoley]

My old RaidMax is 28A on the 12V+ rail. The brand new Thermaltake is only 14?!

So, my old power supply went bad and the new one I purchased is a piece. Is that what your trying to tell me?

I hope your right and my old MB is still good... That would be a nice supprise.

Thanks for the help.

 

[jpoley]

Bump... Still wondering what to try next.

 

[ohiou_grad_06]

I would say try another PSU if someone has a spare. Does the Thermaltake only have one 12v+ rail? Hopefully your old mobo is still good. But I've seen PSU's that didn't give enough amperage kill parts if they aren't quality units. Like myself, I had an MSI board once, had some junk PSU hooked up to it, was on a very very tight budget got some hercules PSU on ebay and used it for a little while, after about a month, the computer was dead. So then I learned quickly to start looking at amperages and what not. Like my dad and I we built mom a pc a few years back, the PSU eventually went out, and dad got a 450 watt. But it was only 17 amps on the 12v+ rail, maybe 16. They started having issues, like the onboard sound went out, then the PCI slots started going bad I think. I happened to have a board with an old chip that was faster than what they had before and a 400 watt PSU that I gave them, and it worked out nicely, but the sad part was the 400 watt unit was rated for 20 amps, and was much heavier. Clearly a better unit.