The 9600GT has 64 shaders. The GT 220 is the card with only 48.
Anyway, the 9600GT is not a bad card, but it's too expensive now for what it is. Considering they are around $90 you are better off getting a Radeon 4850 or nVidia 9800GT. The Radeon 4850 is around $90 and is much faster. The 9800GT can be had for less than $90 and is slower than the 4850, but faster than the 9600GT. Depending on what you paid for it, you may want to return it for something faster if you can
Anyway, the 9600GT will play older games at high settings at 1440x900, but for newer games you will have to probably lower some settings.