Last weekend I took some older components (msi-p45 platinum, e8400, 8 gigs of ram) and built an HTPC by throwing in a 380 Watt antec earthwatts psu and a Powercolor Go Green Radeon 5450 512MB gpu.
Everything appeared to be going fine until I tried to watch an episode of Lost last night. When the action scenes started rolling the video got quite choppy. I have this pc hooked up to a 37 inch 1080p LCD tv (although itunes probably isnt running 1080p, i think they are 720p).
I would have thought this little wonder had enough muscle, but im not thinking of going back and upgrading it to a 5750/5770. Is that too extreme? Is there something between a 5450 and a 5770 that could realistically handle HTPC duties?
Choppy video isn't a fault of the graphics card, since the video playback duties are handled by the CPU (the graphics card you have handles video transcoding, audio bitstreaming duties). I suspect there is a problem with the video itself.
*AMD recommends a 400W power supple for the 5450. Maybe your entire system is not getting enough juice from the psu, causing the video choppiness.
That PSU is certainly not the problem unless it is defective but yes, that card should easily handle HD playback. Could be a problem with the file itself(have you tried other HD video?) or perhaps a software issue. Itunes would certainly not be my choice, try something less bloated/more reliable like VLC.
I have a htpc with a e4500,2.2 dual ,4 gig memory and at one point a 8600gt, that went bad, so had to put in a ati 2400hdpro 128 meg, and that can play mkv blu ray rips. But it was a lot more fussy than the 8600, ALOT.
I use k-lite codec pack full install . That put MPC home theater on your computer, I use that to play my media files. Within the program , I had to select under options, playback , output , old renderer. With the 8600, I didn't have to touch any settings.
That card is meant to do what your asking.
when playing Xvid
cpu 27% utilization
I can verify its not an issue with the video as I have tried other itunes videos and they all experience the same issues. Further these videos played fine when a different video card and psu combo were used 2-3 months ago (4870 and 700 Watt PSU), the only thing that has changed in this rig since then is the new gpu and psu.
Interesting suggestion about the PSU though. I'll try hooking up a more powerful psu and see what happens.
So you don't think the playback at the high resolution is problematic for this card at all?