The 5750 is definatley better. they perform similarly, but the 5750 uses much less power, has dx11, eyefinity if you need it. The flip side is that i costs more money ($150) while the 4850 performs the same in games today but costs $100. If money isn't too much of an issue I'd buy the 5770 tbh. It's only $20 more than a 5750 and performs much better especially if you are going to keep your graphic card. And in your picture that is the gpu and memory clocks (speed) of the ATi graphic card being used. The are "under clocked" (slower speeds then what they are supposed to be) probably because they are idle and they don't need the extra energy, but when they game or do something taxing they'll increase to normal speeds.