Possible PSU issue?

[SweetSorrow]

Hi guys, I have a little problem at the moment which I *think* is related to the PSU, but I am unsure.

Basically, my computer randomly reset during a game, then restarted as normal. This occurred two or three times more after the first time, over a period of a few weeks. On the last occurrence the computer would no longer restart. It would attempt to power up, with lights on and fans spinning, however, power would then be cut after about 1 sec. The power would then remain off for a couple of seconds, and then attempt to restart again with the same result.

I have since removed all non-critical components from the computer (leaving only the CPU, RAM and motherboard connected). However, the same result is seen. I have also tried an old PSU with this configuration and the computer started successfully. However, I have also tried my current PSU in my older computers and it works fine there.

So yeah, I'm a little lost at the moment. Seems my PSU works in other (older) computers but not in mine. But older PSUs still work in mine.


My computer specs are:
CPU: Intel E4300
PSU: Zalman Noiseless 600w
MOBO: Gigabyte 965P-DS3P Pro
RAM: 2x Kingston 1GB DDR2 667
GPU: Powercolor X1950Pro 256Mb "AC" PCI-E
CPU Fan: Thermaltake Typhoon VX
HDD: 3x various size SATA drives
Optical: 1x SATA DVD drive



I hope someone has some idea of what the problem could be!


Thanks!

 

[rammar16]

what is your older PSU

 

[SweetSorrow]

The two older PSUs I've used are an Antec Smartpower 350W and a generic "PT-A350W". They are the only ones I have laying around, and obvisouly can't run the whole system.

Also, just an update.
I've been playing around with it a bit more and if I unplug the ATX 12V cable from the motherboard (using my Zalman PSU), the system will maintain continuous power without restating (won't boot obviously without the 12V).
But as before, when I plug either of the two older ones in it boots up fine. (I used my current PSU to power the GPU so I could see it boot proerly).

Also as I said before, using the Zalman PSU on an older computer it works fine. The motherboard I'm testing it with is an MSI K7N2 Delta. Although I have noted that if I use my old PSU with the 12V unplugged it boots up fine anyway, so I guess this doesn't prove that the 12V works on my Zalman?

Still very much confused!

Edit:
Oh also, I have had a close look at the motheboard and cannot see any dark marks or bulged capacitors

 

[SweetSorrow]

Any ideas anyone? Would really love some input.

 

[rno]

600W Zalman should be more than enough for your E4300 and X1950 Pro.
It really looks like there is something else wrong. Failing RAM, cables etc..

 

[RetiredChief]

Unless you have a DVM this is going to be difficualt to isolate and even then it is hard.

A crystal ball would be nice, or an educated coin toss. You have three options - Failing PSU ( +12V drops off under higher load), The Motherboard ( ie +12 V regulator failing), Or an add on part - Memory, or graphics card. But memory or graphics card should provide an error beep code.

Baring this (explained in next para) the only way to eiliminate PSU is to place the PSU into a system that draws the same, or slightly more Current, or get a PSU that will completely power your system.

Alternative - not good unless you have a fair to good understanding of Electronics and are comfortable with - But you asked.

With a DVM you could monitor the 12V as you power on - does it stay at > 11.5 V. Harder still you could monitor the current on the +12 V 4/8 connector, if it is excessive then the MB ( ie +12 V -> CPU voltage requlator ) is bad. As I said this is hard as you would need an extender cable. Cut the +12 V lines Short them together at each end then connect the DVM (in curent mode) between the to ends. AS I SAID hard - but you asked.

 

[SweetSorrow]

Yeah, I'm pretty sure it's not the RAM since there are no warning beeps. And it shouldn't be the graphics card since it has the same problem when the graphics card isn't plugged in.


I do have access to a DVM, but I don't particularly want to damage the PSU cables, since it's actually still under warranty.

Hmmm, guess I'll have to try and find someone with a computer I can test it in. Which will be hard since I don't know anyone with a recent computer where I am currently staying :S.

Oh well, thanks for the help! Maybe I should just send the PSU off for replacement, and if they find nothing wrong with it, just pay the shipping costs and assume it was the motherboard.

Thanks again.

 

[kenzz0]

If the problem first started when you were playing a game and you eliminated video card by pulling this out that tells me that your PSU might have a thermal problem, one component is unstable with the temperature / load causing the problems you describing. If it was the mainboard the same thing would of happen with the old PSU. Why the Zalman is working fine in your old computer - maybe because it's not reaching that load/temperature limit where the fault is developing. So first I would RMA the PSU and than see how it goes. Cheers and good luck