Vista - Need help with video card

I have a HP Pavillion a6700f pc with AMD Phenom x9150e quadcore processor, 4GB Memory, and NVIDIA GeForce 6150 SE Graphics with Vista 64-bit Home Premium. I'm wondering what I need to do to run WoW on max settings. My guess is get a video card, but I'm clueless about what to get. I've heard when you get a video card you might have to have a power supply, and that's what gets me. I can install a video card easily enough. I recently got a video card and hooked it up but I never could get it to work. The forceware on the installation cd was for 32 bit Vista, and of course wasn't capatible. Can someone give me a hand?

ok two questions
first what kind of card did you get?
second what is your psu wattage?
and could you fill out you system specs
and as to running wow at max....... it won't take much of a card.... my HD3650 could do it just fine so in your case a 9800gt would prolly do it unless you want to switch to ati

You do know that you can go to Nvidia's site and download 64-bit versions of their drivers.

But as you are correct, it is time for an upgrade. if your budget is 200$ or lower, go with an HD 4870 or a gtx 260 core 216 (if you have the power supply for it, i'd say 450w minimum for those).

If your budget is 100$, i have seen some 9800 gt's that get to about 100$ but then something like a 9600 GSO 768 mb or an HD 4650 or 4670 would be your best bet.

AND... if your budget is all get out as hell, then go for a gtx 275 or better.