Hd / Blu-ray playback

Not very well. I suggest a minimum of HD4350 or HD5450 graphics card to do that.

and in all reality, the onboard HD3200/3300/4200/4290 will help play back these files just fine (also the NV IGP's work just as good)

the X4500 doesn't do so good, but the IGP in the new i3/i5's do a decent job

Based on the following review, the best video card for video playback is the HD 5570. It doesn't use much power 19w while gaming, 13w for video. The HD 5450 is a less expensive alternative with slightly lower video quality scores and power consumption.

http://www.xbitlabs.com/articles/video/display/radeon-h...