Power supply faulty, or motherboard?

dennisresevfan

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Feb 26, 2010
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I'm about to build a new pc system and I want to make sure my power supply isn't going to damage it.

It's a new power supply. But when it was installed into my current system, it destroyed my graphics card.

I believe this was entirely due to the guy installing it putting a PCI-e power cable into the EPS12v socket in the motherboard. I have since discovered that this can cause serious hardware damage.

After replacing the graphics card, the system still has a problem. With the damaged GPU, it would reset itself or freeze when I tried to open files in Windows, go on the internet, etc.

With the new GPU (confirmed to work ok on other systems, and uses same drivers as the old one), the system will still reset or freeze, but ONLY when attempting to play a game or play a video in windows media centre.

Music doesn't cause a problem even in media centre. 2D games (I emulated Symphony of the Night on a playstation emulator to test this out) do not cause a problem. But when I try to play anything more advanced, it usually freezes as soon as gameplay begins.

Oblivion freezes when I load a game. STALKER freezes the system as soon as I click on its icon! Presumably this is something to do with the intro videos loading up.

Anyway, my system was checked over at a repair centre, and tested out with "PC check" software. The original GPU is definitely damaged as it has the same problem in other systems. The new GPU is apparantly ok. Apparantly the CPU, PSU and RAM tested out ok as well. But then again so did the motherboard. That's almost everything in the system, and yet there is definitely a problem!

So. Basically, what do you think the problem is?

If it's the motherboard, no problem. I'm getting a new one.

If it's the power supply, then that is a big problem and I must RMA it.
How can I find out which it is? I don't have a spare motherboard to test out the PSU and other components with.

Then again I'm only worried about the PSU DAMAGING the new system. If it just has a resetting problem then if I see it still occuring, I'll RMA the PSU.

Can a PSU damage a system assuming it's wired up to it properly, and the voltages are all fine? (Which they are)

I should add that my components are not overheating. I checked.

In addition... The old GPU was electrically fried. Is there any chance of the oven baking trick working in this situation?

Also, if I tried baking it, and I put it into my system, is it possible for a damaged GPU to damage the rest of the system, or not?
 

If you look closely at the PCIe and the EPS connectors, you will notice that they are wired opposite to one another. This means that you will be shorting 12 volts to ground if you plug either one into wrong place. If you were lucky, the PSU would have sensed a short and electronically shut itself down before any damage occurred. I wouldn't use that PSU. The protection circuits in it are inadequate.

What kind of PSU? In fact, complete system specs - including brands and models?


That is a sign of inadequate power. A 3D load on a graphics card just about doubles its power requirements.


Our standard checklist and troubleshooting thread:
http://www.tomshardware.com/forum/261145-31-read-posting-boot-problems

Try to borrow a DMM to measure the voltages. Yellow wires should be 12 volts. Red wires: +5 volts, orange wires: +3.3 volts, blue wire : -12 volts, violet wire: 5 volts always on. The gray wire is really important. It should go from 0 to +5 volts when you turn the PSU on with the case switch. CPU needs this signal to boot.

You can turn on the PSU by completely disconnecting the PSU and using a paperclip or jumper wire to short the green wire to one of the neighboring black wires.

This checks the PSU under no load conditions, so it is not completely reliable. But if it can not pass this, it is dead. Then repeat the checks with the PSU plugged into the system.


Possible? Yes. Likely? No.
 

dennisresevfan

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Unlikely, no? You mean it's LIKELY to damage my system? Or did you mean "Likely? No."?

Ok, system specs:

Power supply: Corsair 950TX (950W, 78A single 12V rail)

It supposedly has overvoltage protection etc...

Processor: Core 2 Duo E6700 2.66Ghz 1066FSB dual core
Motherboard: ASUS SKT-775 P5B S/L 1066FSB
RAM: OCZ 800Mhz DDR2 4 X1GB
Graphics card that got damaged: Nvidia (ASUS) 8800GTX
Graphics card I'm using now: Nvidia 8800GT
Hard drives: Samsung something or other. Not important really. I doubt these are damaged since I can access data just fine.
 

dennisresevfan

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I wasn't aware bumping was allowed, so I thought I'd ask in a more relevant forum.

This one has power supplies as part of the title, so...

This is also more specifically about the power supply itself. I don't understand how it could not be giving out enough power if the voltage readings look perfectly ok in both BIOS and HWmonitor.
 
The general rule of thumb is its ok to bump if you havent had any more post in 24hrs.

I say this because it would help people to see what we already might have ruled out and what has been discussed.
 

dennisresevfan

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Ah, ok, thanks for that. I'm used to a forum where you're basically never meant to do it at all.

Anyway, how do I actually take reading from the coloured cables, even if I get one of those meters?

I mean... I can't see how I have access to anything apart from the actual power connectors at the end of the cables, and those cables are jacketed. Opening them up would definitely void the warranty.

Should I just RMA the bloody thing and risk paying for postage costs?
 
With a volt meter i use a paper clip taped to the leads with that you can fit in the back of the connectors and take readings. If its newegg if you call them they usually will pay for postage.