1) Right off the bat we see the ATI Radeon HD 5450 run well below that of the NVIDIA GeForce GT 220 or even the previous-generation Radeon HD 4650
2) Even those on a tight budget would be much better off buying a graphics card for $60 USD or more like the NVIDIA GeForce GT 220 that is much more capable...
3) If you are just interested in supporting AMD for their open-source efforts, this is a fine card but obviously with even the proprietary Catalyst driver producing low frame-rates, do not expect much...
4) There is also video playback acceleration via XvBA (the X-Video Bitstream Acceleration) architecture, but that is currently buggy in the latest driver revisions
5) Anyone interested in a low-power, passively-cooled graphics card for a HTPC / media PC still would be much better off getting any NVIDIA