MSI Nvidia GTX 670 - No Power/Post with both 6-pin cables connected

[solman79]

Hi all,

I was hoping some of you experts could help me out with this. I have the following config:

Mobo: Asus M5A78L Series
CPU: AMD FX-6100
RAM: 2x4 GB Kingston 1333 Mhz
GPU: MSI Nvidia GTX 670
HDD: Samsung 80GB
PSU: OCZ 650W

Today, my computer would not start. When I pressed the power button. On opening the case, here's what I observed.

If I pressed the power button, the CPU/Case fans/lights would start for just a second and then stop. No POST/Power, nothing.

So I took the components out and tested as follows:

PSU: I tested using a digital PSU tester and found that all voltages were within the normal parameters. So the PSU is fine.

CPU, single stick of RAM, and HDD - POST successful.
CPU, both sticks of RAM, and HDD and Optical Drive - POST successful
CPU, both sticks of RAM, HDD, ODD, and Graphics card - Power for a second and no POST.

Here's the interesting bit. The Nvidia GTX 670 has 2 x 6-pin slots for power. When I do not connect any power, the system completes POST but obviously the card is not detected. If I connect just one of them (the left one), the system posts. But if I connect both, the system does not post.

I tested both the 6-pin connectors from my PSU and they are fine. Could there be an issue with my GPU? Secondly, why would it post with one power connector, and not let the system power on for more than a second when the second one is connected?

Any ideas? If you're certain my card is fried, are there any repair options? It's just 3 months old and I really don;t want to spend £ 300 on a new card right now

Best Regards,
Sol

 

[squirrelonfire]

All I can think off is 1 of your 12V rails is broken. Try using different 12V cable.

 

[solman79]

All I can think off is 1 of your 12V rails is broken. Try using different 12V cable.

Wouldn't that show up in the PSU test? I tested both the 6-pin connectors.

 

[bignastyid]

Wouldn't that show up in the PSU test? I tested both the 6-pin connectors.

Your standard psu tester does not test under load which is where most psus fail.

 

[bignastyid]

You either have a failing gpu or a failing power supply. Do you have another psu to test with?

 

[solman79]

You either have a failing gpu or a failing power supply. Do you have another psu to test with?

Hi Big - Yes, in fact, I just finished testing with another PSU I borrowed from a friend. Same results. So I guess it's a GPU fault.

I opened up the GPU and can see no blown capacitors or any sign of burn damage. Any ideas?

 

[bignastyid]

Probably an internal short. I have many bad video.cards that showed no sign of physical damage.

 

[solman79]

Probably an internal short. I have many bad video.cards that showed no sign of physical damage.

I've been searching online, but can't find any detailed info on this specific problem, and how to fix the card. Before I resign to loosing a nice £300 card and having to purchase another, any thoughts or known links on fixing this? I've isolated the problem to the points that go from one of the two rails, but since they're not soldered in like the capacitors, not sure how to proceed.

 

[bignastyid]

The card should be covered by warranty, you shouldn't have to buy another. The card is not repairable. In the UK MSI video cards have a 3YR warranty and your card should be covered. http://jkarma.msi.com.tw/Customer_Service/

 

[solman79]

The card should be covered by warranty, you shouldn't have to buy another. The card is not repairable. In the UK MSI video cards have a 3YR warranty and your card should be covered. http://jkarma.msi.com.tw/Customer_Service/

Thanks for that link. I called their customer service and I'll need to take this up with the vendor directly (dabs.com). Hopefully they'll repair or replace my card.

My rig, although modest, is still running on parts from reputed manufacturers. Are there any precautions you would recommend to avoid this sort of thing in future?

 

[bignastyid]

Not much you can do. I buy only high quality hardware for my builds and still get the occasional failure.

 

[solman79]

Not much you can do. I buy only high quality hardware for my builds and still get the occasional failure.

You were right about an internal short in the card. Apparently what's happening is that the second 6-pin power connector is causing the +12V to get shorted via one of the Ground pins, and causing the PSU to behave as it would in event of an electrical short.

Luckily for me, it's under warranty, but I need to go via the vendor. Hopefully it won't take too long.

 

[bignastyid]

MSI is usually fairly quick on their RMA's.

 

[muhv]

You were right about an internal short in the card. Apparently what's happening is that the second 6-pin power connector is causing the +12V to get shorted via one of the Ground pins, and causing the PSU to behave as it would in event of an electrical short.

Luckily for me, it's under warranty, but I need to go via the vendor. Hopefully it won't take too long.

There is also article about MSI see whether it affects you.
http://www.tomshardware.co.uk/MSI-GTX-660-670-overvolting-PowerEdition,news-40278.html

 

[solman79]

There is also article about MSI see whether it affects you.
http://www.tomshardware.co.uk/MSI-GTX-660-670-overvolting-PowerEdition,news-40278.html

Thanks for that, it was an interesting read, especially for a relatively new builder like myself. Luckily my card does not have that issue. It's not a power edition. It's the stock...boring looking one with just one fan at the side