Lowest power consumption graphics card?

[Steve_Y]

I'm not a gamer and I've been very happy with my 790GX motherboard's onboard graphics until now, but I'm planning on upgrading to a monitor with a higher resolution than it can support.

I'm cooling the PC with a single low speed fan and would like to keep the increase in power consumption and heat down to a minimum. That's much more important to me than the card's performance, features or price.

Can anyone suggest the lowest power consumption card that can provide a 2560 x 1440 display?

[ces]

Look at the Radeon 5450. It is the lowest power video card around and if you check the specs, it probably does what you want. It is something like 7 watts.

[kiblams]

Search in google for:

ASUS HD 5450 SILENT 512MB DDR2 DVI HDMI VGA Out PCI-E Low Profile Graphics Card

Low profile fanless DX11 card which will do your resolution on the DVI port.

[mczak]

Are you sure your board can't support dual-link DVI? The 790GX chipset certainly does, though it might indeed be possible some motherboards don't.
If it doesn't, I think the 5450 suggested by others is fine. Just make sure it's fanless, and personally I also wouldn't touch any ddr2 versions - you sacrifice literally half the performance for a minimal gain (if any) in cost and power consumption.