hey..can you help me too? I happen to have the same desktop as you lol. Would you suggest a sapphire 4650 or sapphire 4670? Those are my absolute only options. I'm just afraid that with the 4670, my computer might explode. I already got the powercolor 4650 and it worked fine, but I found out it sucks.
I was about to buy a 4650 because it said "25 W Consumption" so I don't think it will fry your computer. And the 4670 should be on the same range of Power consumption.
Plus, our friends in here say a 5570 can be powered by a 250W Power Supply, there will be no risk I bet with the 4XXX ;P
Buuuut, let see what our fellow gamers think of it, can a 250W Power Supply bear a 4650 or 4670?