Well Im pretty new to this but I recently completed my htpc build and not only with 1080p but also blue ray. I have a choice to run my sound through 5.1 speakers or through the hd cable.
silverstone gd1 case with card reader
Asus p5w 975x deluxe home motherboard included also was a remote and on board wifi
Asus 3650 silent 512mb full hd and blue ray decoder
Intel Q6600 @ 2.4 set up with speed step 1.5 to 2.4+
crucial ballistic ddr2 @ 800mhz X 4
lg blue ray drive and burner
Silverstone Element 500wt psu
xp pro 64 bit
actic freezer pro cpu cooler
lead drive wd 320
second samsung 1 TB
third Samsung 1 TB
logitech G-51 5.1 speakers
logitech LX710 keyboard and mouse
LG 37" full hd LCD TV
I have had this set up togather for a couple of month now and it has done nothing but impress from creating web pages to rendering video, graphic design and play games ie call of duty 4 and pro street sounds like a run on sentence but its funny i can do most of these tasks at the same time. The Blue ray and hd quality is deffinatley noticeable over standard hd. You might think this would run hot but it doesnt vga temp usualy about 46c and mb about 45c
the cpu fan has never seen 1000 rpm, the cpu temp around 22 to 28c and I swear this is quiet you have to strain your ears to hear it running. Anyway hope this helps that from the comfort of my chair or couch i can do anything work, games, vids without having to sit at a desk or workstation its great to have these advantages.
I woudl be weary of AMD with 1080P stuff. My AMD 4400+ sometimes has issues with the 720p stuff and 1080i stuff, let alone 1080p. I've actually over clocked it a bit too.
The onboard GPU on the motherboard does most of the video decoding. I have no trouble playing 1080p. The processor is a X2 4600+ but it is barely loaded during playback. This thing can even play some older games at 1080p fine.
Project: Black and White i7 920 D0 | 3 x 2GB DDR3 | EVGA X58 SLI LE
XFX 4890 | Corsair HX750 | Corsair Obsidian