Perhaps if you review specs. On the two GPU's you can make a decision on which one suits your needs the best: GeForce GT 240 Specifications And Hardware : GeForce GT 240: Low Power, High Performance, Sub-$100 Specifications : Nvidia's GeForce 9600 GT Tested
Keep in mind The GeForce GT 240 will be replacing the GeForce 9600 GSO and GT.
Gigabyte's GV-N96TSL-1GI runs at the reference GeForce 9600 GT clock speeds, but it boasts the 'silent cell' cooler that produces no noise at all. On top of this, Gigabyte has graced the card with a full gigabyte of RAM.
Sporting a 256-bit memory interface and 64 shader units, the GeForce 9600 GT has a reputation for being a very fast card for the dollar.
Side by side comparisons: GeForce Vs. GeForce? The Sub-$100 Market : GeForce GT 240: Low Power, High Performance, Sub-$100
Test System And Benchmarks: Test System And Benchmarks : GeForce GT 240: Low Power, High Performance, Sub-$100
It looks like the GeForce 9600 GT is putting up a pretty good fight against the GeForce GT 240 cards. Although, for all intents and purposes, the slight difference can be called a draw. The GeForce 9800/8800 GT easily walks away with a win here, and the GeForce 9600 GSO also competes well, but ultimately falls short of the newer cards.
Hope this helps.