Whats a good low profile video card?

I currently own a Dell xps 210. It is a slim model and therefor requires a low profile video card. Right now I have a Radeon sapphire HD 4350 and it is now outdated. Whats a good graphics/video card that would work on a dell xps 210? Price is not an issue I just want the best one available for a dell xps 210.|||The Radeon HD 6450, significantly faster yet uses less energy, also no fan so it's quiet|||Your computer has a 275W power supply, most good graphics cards require a 400W power supply. Nvidia GT 520 and AMD HD 6450 would work, but they are pretty weak.|||6670 > 5670 > 6570 > GT 240 > GT 440 > 5570