I've got a somewhat older GPU lying around that I decided to set up for mining purposes, as where its located I pay an all-you-can-eat electricity plan. Its running Win7 x64, ati stream v2.2, and poclbm but I never see it use more than 1% utilization on the GPU and its only going at 990khash/s max.

The card is currently running default speeds, latest Catalyst drivers, and nothing but Aero using the GPU at the moment.

Any ideas why its not using the GPU more?

EDIT:
I found out that it was reading my CPU as device 0 and my GPU as device 1. The guide I followed told me to set the device to device 0.

I think most people don't check wattage use at all, they just assume that because they are using a GPU it will be profitable. A lot of people with old ATI cards and pretty much any Nvidia card are probably paying more for the bitcoins by mining than they would if they bought them.

You need to have some kind of measurement tool inline with the power plug going into your computer.  You can guess how much your computer brings down based on manufacturer specs, but you'll never really know until you measure it.