Upgrading Video card?

Well I have a farely old computer.

It's a Dell Inspiron 531.

Basically I'm just upgrading my video card to run Aion at decent graphic settings without lagging down to 8fps in citys.

Aion GPU Requirements:

NVIDIA Geforce 9800 GT, AMD Radeon HD 4850 or higher

I went through tons and tons of video cards but it's hard to find a video card that will work with my 290w power supply and still put out good power. The 9800GT is a little old and the nvidia website told me that my computer could run a Geforce GT 630 which I figured would be better then the 9800 GT but on Newegg the reviews on the card say it's NOT a gaming card. Lol.

My comp currently has 4gb ram, win 32 bit.

Here's link to MOBO.

http://support.dell.com/support/edocs/systems/insp...

I just really need help deciding because if I'm going to buy one I want one that will be the best bang for my buck and still run games decent with only a 290w psu.