I have a 9800GTX/GTX+ myself and it runs like a charm. It looks like the 9800GT only requires 1 6-pin connecter for power which makes your life easier. My card requires 2... Not a big deal, but that's a lot of power for a video card.
Also note, once you go up to the $130+ range you get into the GTS 250 and such:
http://www.newegg.com/Product/Produc...82E16814130513
I would probably recommended one of the big names for a GPU... newegg carries a lot of unknown brands...