Advice on video card power requirements

BigP

Hello all,
I'm looking to upgrade my year old Dell Dimension 9100's video card from an ATI X600 256MB Hypermemory to a GeForce 7900 GS 256MB.

My first question is, is it worth doing?

My second is, will my 375W power supply be sufficient as most manufacturers' specs suggest a 400W PSU to run the card. I currently have 2 optical drives and 2 HDDs ,nothing else fancy. I was wondering does anyone have any experience with doing this?

Thanks in advance.

stevejazzx

so you have a free pci-e slot on your mobo?

the 7900gt would use up to about 150-200 watt and would need to be powered directly from your psu via a pci-e cable

375w psu would work but it is low.
A new PSU would sort you out something around 500-600watt
600 watt would future proof you but then your rig is probably not that upgradable but it is definitely worth upgrading to a 7900gt if you can pick up a 450 watt psu from boards you'd be in business

BigP

stevejazzx wrote:

so you have a free pci-e slot on your mobo?

the 7900gt would use up to about 150-200 watt and would need to be powered directly from your psu via a pci-e cable

375w psu would work but it is low.
A new PSU would sort you out something around 500-600watt
600 watt would future proof you but then your rig is probably not that upgradable but it is definitely worth upgrading to a 7900gt if you can pick up a 450 watt psu from boards you'd be in business

Yes, I have a free pci-e slot. And it's the 7900gs I'm aiming at.

Ideally I would like to get a more powerful card and new PSU but from what I've read, there seem to be many issues with upgrading a Dell PSU. That's why I've gone for a mid-range card in the hope that my puny 375W will support it.

stevejazzx

7900 gt/gs little difference

does your psu have a spare pci-e power cable?

what is your processor?

375 should be enough

http://www.extreme.outervision.com/PSUEngine

always seem to undervalue a bit though

BigP

stevejazzx wrote:

7900 gt/gs little difference

does your psu have a spare pci-e power cable?

what is your processor?

375 should be enough

http://www.extreme.outervision.com/PSUEngine

always seem to undervalue a bit though

Thanks stevejazzx.

I used the PSU engine and it says that my current system uses 274W and an upgrade to a 7900gt/7900gs/7950gt would bump it up to 314W. I take it then that this would be OK?
I don't have a dedicated spare pci-e power cable but it would appear that the cards come supplied with a twin molex to pci-e connector.
Oh, and the PSU has 2 12V rails, 12VA and 12VB. Both have individual amps ratings of 18A and a combined of 30A. Does this help?

Any advice would be welcome before I buy one and possibly fry my PSU or worse!!!

Psycopat

stevejazzx wrote:

7900 gt/gs little difference

the GT would be a good bit better than the GS but im sure moeny is a factor and the GS is just Cheaper