I would like to know what cards will playback 1080p bluray backups, in MKV format, I switch my htpc from my 1.8ghz duo core mac mini that played boxee and plex playback of almost all bluray rips in 720p and a few drops of frame rate of 1080p encoded files.

I wanted to use the mac mini as a desk computer and switch out my windows box as a htpc

Windows box is as follows

quad core 2.8ghz intel Q9550
4 gigs ddr2 ram
32Gig raptor sata 10K rpm
gigabit connection
ATI HD3450 with dvi to hdmi connector
windows up sp3 updated
Boxee

I cannot not get playback of HD files smoothly on my hd72 projector, however on a 19" 1280X720 dvi monitor playback seem flawless

I don't know what is the weak link, Should I upgrade the video card to something with HDMI and 7.1 intergrated sound

Any suggestions. this computer should be a work horse and shouldn't struggle to play back HD content.

Any suggestions would be a help

its got to be your display settings, try different display refresh rates. your pc is better than mine on all fronts, and mine plays 1080p no problems.

also try installing MPC-HC and reclock (google them) and see how that goes.

Find out your answers here:

http://www.avsforum.com/avs-vb/forumdisplay.php?f=26