upgrade my desktop with a card?

I cant get my self you pay and build a pc my self even tho i some day want too. is it worth putting a good graphics card in my budget pc so it can play some new games. keep in mind i got the computer for $329. if so what are some cards that are a good bang for the buck. i had a older computer with a 9800gt that just recently burnt out. i was able to play crysis 1 on high with some extreme.........only while using a xbox 360 controller. when i tried to play with the mouse and keyboard the frame rate dropped like crazy. This was probably due to the slower movement so the gpu didn't have to draw out the visuals that fast.

anyways....

i have a stock hp desktop (7 months old.)

AMD APU A8-5500 2.8ghz boost to 3.5ghz. dual core/4 logical processors.

8gb ddr3 ram

300 watt power supply.

2tb hdd i believe its 7200 rpm

GTX 750ti is a good option without having to change the psu, while giving you dx 11 ability and being at least 4x faster that 9800gt.

This, you can get those GPUs pretty cheap (starting from 120$)

Are you sure the 9800GT was broken and it wasn't something else in the PC? Might be worth trying.

@kraken2109: completely dead. as soon as i took the card out and plugged my vga cable into the original onboard video it work again. before removing the card i tried to rescue it but there was nothing i could do.