power/heat issues with Nvidia card

[Canuck1]

I am just wondering if anyone can diagnose or figure out a problem I'm having with a used video card I just got.

It's an Nvidia 7950 GT and it might not be typical of this card but I am getting a message when I boot up and shut down of it not having enough power. I inserted the card in the PCI-e slot and pushed the fan pin into the motherboard's pins and thought everything was done right. But, when I booted up, there was a message from the Nvidia 'panel' (?) that it might need a supplementary power cable. Huh? I opened my box up and looked at the PSU and couldn't even find a cable from it that would fit (into the black 6 pin bracket at the end of the card).

The video card has an aftermarket Zalman cooler and it seemed to be working.

Can anyone tell me what would cause power issues? I also could smell something burning at one point so I shut the computer down and took out the card. There doesn't seem to be anything burnt but there were a few very warm components. I don't want to fry this card as I just got it and as far as I know, it was working before for someone else.

Additional info if relevant/helpful:
Asus A8N32-SLI Deluxe motherboard
AMD Athlon X2 4200+
Seasonic (Super Tornado) 400w PSU

Any ideas?

 

[pauldh]

The 7950GT requires more power than the PCI-e slot provides for it. You MUST plug in the 6-pin PCI-e power connector to use the card. Your PSU is an older ATX PSU.

What is your power supply? Look at the label on it and see how many amps on the 12v rail. If it has 25 amp or above then you can buy an adaptor cable that uses two four pin molex connectors from your power supply (like the CD-rom drives use) and has a 6-pin pci-e plug on the other end.

If you have an old PSU with an underpowered 12v rail, then you need a new power supply (which has the PCI-e 6-pin connector).


edit: Your seasonic has a single 22 amp 12v rail. You may still get by with just the adaptor cable but 22 amp is cutting it close for the 7950GT which uses more power than the 7900GS. I'd be more comfortable with 26 amp.
http://www.xbitlabs.com/articles/video/display/geforce7950gt_3.html

 

[Blacken]

Sounds like you need a 4 pin to 6 pin converter if you can't find a 6 pin stemming from the PSU.
Newegg sells them for pennies;
But first you may want to trade the 7950 out with another and sniff around for that smell to detect if it is the videocard or another component (could be the PSU as Paul has found that it may not be sufficient for the 7950).

 

[Canuck1]

You guys are right on the money. I got a 4-pin to 6-pin adapter but should I even bother now? The Seasonic PSU is only 22 amp 12v rail as mentioned.

Am I okay to use this PSU when it's at the limit for the video card and then buy a higher wattage psu or should I use the old video card (very low end ATI card that doesn't need the adapter) until I buy a higher wattage psu?

Lastly, which one should I get and how many watts do I need (min.)? If I should get a new one, I'd like a modular PSU and was hoping that 500 watts is enough. Many are around 28 amps on the 12v rail min.

I tried the same computer with the older video card and it's working fine with no burnt smell so I hope that was only temporary due to the insufficient PSU being used and/or lack of the 4-pin to 6-pin connector/adapter.