# [SOLVED] PSU issue?



## thetanman101 (Nov 26, 2011)

I've got a Dell Home Studio 540 with the Intel Core 2 Quad processors. Running Vista home premium. It's several year old.

It would not start. I pulled it down, about to start a multi-meter test on it. Hit the start button on it for the twentieth time and it cranked up. Hard to test for what's not working when it cranks last second. Ran ok for another week or so.

But now, once again, it won't start. Power light is on on back of the PSU. I did a multi-meter test on the 24 pin motherboard connector. The PSU fan does kick on when shorting the #15 and #16 pins together. The only pin that came back below tolerance was pin #9, the +5 volt stand by (purple) wire, which read at 4.45 volts DC. This isn't much below the standard five volts, could this have an effect on the cpu not starting?

I have also grounded the two wires from the start button together to rule out a bad button.

If the low purple wire is not likely my culprit, then I cannot consider the PSU faulty. Where would I look next?

Thanks in advance, and please forgive my noob ignorance. I'm learning this as I dig into it.

-Tanner


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## Tyree (May 10, 2009)

*Re: PSU issue?*

I would not rule out the PSU. Starting intermittently is a sign of a bad PSU and any OEM PSU over two yrs. old is suspect.


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## thetanman101 (Nov 26, 2011)

*Re: PSU issue?*

Well if the PSU was the issue wouldn't it show in not providing the necessary voltage to the required circuits when grounded on?


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## Tyree (May 10, 2009)

*Re: PSU issue?*

Testing a PSU with no load is not really conclusive. Is the hardware the original configuration? What is the Brand & Model of the PSU?
It's also possible the connections were dirt and unplugging and reattaching the PSU to Mobo harness started making good contact.


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## thetanman101 (Nov 26, 2011)

*Re: PSU issue?*

It's all original. Sticker reads LiteOn Model no. PS-6351-2 D1 ROHS 350Watts


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## thetanman101 (Nov 26, 2011)

*Re: PSU issue?*

So what would be the next path of trouble shooting you would suggest?


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## thetanman101 (Nov 26, 2011)

*Re: PSU issue?*



Tyree said:


> It's also possible the connections were dirt and unplugging and reattaching the PSU to Mobo harness started making good contact.


 And unplugging the harnesses hasn't had any effect. The first time, when it started working again, was before I had actually unplugged anything. It has been inoperable ever since the second time.


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## Tyree (May 10, 2009)

*Re: PSU issue?*

Do you have or can you borrow a known good PSU to try?


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## thetanman101 (Nov 26, 2011)

*Re: PSU issue?*

No. If the PSU was faulty under load, would it not at least attempt to power up?


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## Tyree (May 10, 2009)

*Re: PSU issue?*

Not necessarily. If it's failed it will do nothing. If it's faulty it may or may not boot the PC.


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## Amd_Man (Jan 27, 2009)

*Re: PSU issue?*



thetanman101 said:


> No. If the PSU was faulty under load, would it not at least attempt to power up?


I have dozens of dead power supplies that will still light the motherboard LED, spin the cpu fan but little else.


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## Tyree (May 10, 2009)

*Re: PSU issue?*



Amd_Man said:


> I have dozens of dead power supplies that will still light the motherboard LED, spin the cpu fan but little else.


And why do we all keep all of those dead PSU's in our shops????? :doh:


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## Amd_Man (Jan 27, 2009)

*Re: PSU issue?*



Tyree said:


> And why do we all keep all of those dead PSU's in our shops????? :doh:


Here in Toronto I have to pay to dispose of any electronics parts. I can put them in the garbage with a "electronics disposal bag".


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## thetanman101 (Nov 26, 2011)

*Re: PSU issue?*



Amd_Man said:


> I have dozens of dead power supplies that will still light the motherboard LED, spin the cpu fan but little else.[/QUOTEy
> They still supply correct output voltage as mine is? Would going back with original equipment probably be my best choice to avoid incompatibilities?


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## Tyree (May 10, 2009)

*Re: PSU issue?*



thetanman101 said:


> They still supply correct output voltage as mine is? Would going back with original equipment probably be my best choice to avoid incompatibilities?


You have made no previous mention of replacing/upgrading from the original hardware configuration. What changes have been made?
Basically you have a low quality PSU that is several yrs. old and probably underpowered.


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## Rich-M (May 2, 2007)

*Re: PSU issue?*



Tyree said:


> And why do we all keep all of those dead PSU's in our shops????? :doh:


Because unfortunately we might be pretty sure,but seldom positive!


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## thetanman101 (Nov 26, 2011)

*Re: PSU issue?*

It is all original. That's why I ask if I should go back with the same, or will i just end up with this same issue in a couple of more years? You say it's likely underpowered, what might I be looking to go back with? I need to do some hunting to see if I can find one local.


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## thetanman101 (Nov 26, 2011)

*Re: PSU issue?*

Corsair - Gaming Series 600-Watt ATX CPU Power Supply - GS600
Looking at this as an upgrade, but not sure if it would be compatible?

Dynex&#153; - 520W ATX CPU Power Supply - DX-520WPS
This one looks to be compatible.


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## Tyree (May 10, 2009)

*Re: PSU issue?*

We normally don't recommend the GS Series Corsair but it should be suitable for your needs but you can do much better for less money.
More power, better quality and 5 yr.warranty for $80: Newegg.com - CORSAIR Enthusiast Series CMPSU-650TX 650W ATX12V / EPS12V SLI Ready 80 PLUS Certified Active PFC Compatible with Core i7 Power Supply


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## Rich-M (May 2, 2007)

*Re: PSU issue?*



thetanman101 said:


> Corsair - Gaming Series 600-Watt ATX CPU Power Supply - GS600
> Looking at this as an upgrade, but not sure if it would be compatible?
> 
> Dynex™ - 520W ATX CPU Power Supply - DX-520WPS
> This one looks to be compatible.


Dynex is really bad junk.


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## Amd_Man (Jan 27, 2009)

*Re: PSU issue?*



thetanman101 said:


> Amd_Man said:
> 
> 
> > I have dozens of dead power supplies that will still light the motherboard LED, spin the cpu fan but little else.[/QUOTEy
> ...


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## thetanman101 (Nov 26, 2011)

*Re: PSU issue?*



Tyree said:


> We normally don't recommend the GS Series Corsair but it should be suitable for your needs but you can do much better for less money.
> More power, better quality and 5 yr.warranty for $80: Newegg.com - CORSAIR Enthusiast Series CMPSU-650TX 650W ATX12V / EPS12V SLI Ready 80 PLUS Certified Active PFC Compatible with Core i7 Power Supply


 
Good price. No worries on this one being compatible? Any issues with returns at this site if it doesn't turn out to fix my problem?


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## Rich-M (May 2, 2007)

*Re: PSU issue?*

A straight refund carries a restocking charge at Newegg of I believe 15%.


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## thetanman101 (Nov 26, 2011)

*Re: PSU issue?*

compatible with an Intel Core 2 Quad?


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## Jr_pomonero (Nov 28, 2011)

You may want to test the PSU on another computer. It could also be that you motherboard could be bad. The best way to find out is to test the PSU on another pc


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## Rich-M (May 2, 2007)

*Re: PSU issue?*

Interesting thought and actually good idea.


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## thetanman101 (Nov 26, 2011)

*Re: PSU issue?*

It would be if I had spare cpu's laying around. I ordered it, and I'm still on the fence whether it's the actual problem do to mine putting out appropriate voltage. Guess I'll fall back to the old parts swapping routine. I'm just hoping it's not the mobo as swapping that out appears daunting.

I will update with the results. Thanks guys.

-Tanner


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## Tyree (May 10, 2009)

*Re: PSU issue?*

You can give the Mobo a basic test. Remove all the RAM, boot up and listen for any beeps from the Mobo speaker. No beeps indicates a Mobo problem.



thetanman101 said:


> Good price. No worries on this one being compatible? Any issues with returns at this site if it doesn't turn out to fix my problem?


No worries on compatibility.
On the slight chance it doesn't resolve the problem you still have a top quality PSU.


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## thetanman101 (Nov 26, 2011)

*Re: PSU issue?*

I want to thank everyone for their guidance. It appears that you have guided me in the correct direction. Despie passing the voltage checks, replacing the PSU has corrected my issues. And boy does that new PSU have tons of extra hookups and a mile of extra wire! Thanks again!
-Tanner


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## Tyree (May 10, 2009)

*Re: PSU issue?*

You're welcome and we're glad we could assist you in resolving your problem.


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## Rich-M (May 2, 2007)

*Re: PSU issue?*

Great why not mark this solved in the first post under "Thread Tools" in the first post.


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