I upgraded our current HTPC with an ATI 5770 a while back.
I normally go for the nVidia cards, but the 5000 line from ATI had something that fit perfectly in the HTPC: Full HD audio bitstream output through the HDMI output. While we don’t have a receiver\multi-speaker setup [yet]…I figured this would still be a better card than what was already in there – an nVidia 8800 series. I like the jumbo, 2-slot cooler on the ATI model too- hoping to keep the inside of the case cooler. I had the HDMI straight to the TV, then back out to the pair of speakers that have been powering the whole setup.
There were 2 initial issues with the setup – HDMI overscanning (where the image doesn’t fill the entire TV screen, even though it is outputting 1080P, and the TV receives full 1080P. Corrected in Catalyst Control Center) and the dynamic contrast issue (by default DC is turned on- but produces unwanted “choppiness” on some TVs when the overall darkness of the image changes, the card overcorrects. Turning this off is done in CCC and has no ill effect on performance). Once these were resolved, everything was perfect*, and has been for several months now.
The only lingering issue(s) are with the TV (I think). Sometimes, if we turn the TV off, but leave the PC on, come back after a while and turn the TV back on, the screen will remain black…as if the PC is stuck in the “turn the monitor off to save power” mode. This is alleviated by switching inputs on the TV, or unplugging and re-plugging the HDMI cable. The other, and far more frequent issue is from a cold boot, sometimes there is no audio. This is fixed in the same manner as above, but due to its frequent-ness, it was not making my Wife very happy. So for now, I re-enabled the onboard audio and am using that as the primary source. I am hoping that once we have a receiver with HDMI inputs this problem will not show again. I’m wondering if there is a fix in the CCC or HDMI audio driver, but I will pursue those when the time comes.