Capture takes very little CPU. Playback depends. My system has a 3GHz P4/HT and a 6200 AGP card. I feed it into a Mitsubishi HDTV via DVI at 1080p and it works pretty well. I use the PureVideo decoder and it runs 20-30% CPU on playback. I had to fiddle with the PureVideo settings a little and I still get a bit of flicker on fast panning but I'm pleased (and a bit surprised) at how well it works.
I tend to think the hardrive system is important as you add more clients and capture cards. I am going to convert my recording drive to a raid 0 array for my next upgrade. A strong cpu is a good idea if you will be doing any re-encoding of video on the system.
If I buy a core2duo machine (P965 chipset) with a HVR 1600 tuner card and a Nvidia 7600GT video card, is this sufficient for HD? I've been reading and it sounds like the video card has to be a higher level. I didn't want to spend so much and was hoping the 7600GT would be sufficient. I read here that people have a lot of luck with ATI cards but I tend to think the Nvidia (and Purevideo) will be good enough.
As for the CPU, I was thinking of the E6300 but I'm not sure if I should wait until next month. It sounds like both AMD and Intel are going to have discounts on their processors.
Btw, another reason for having a seperate machine for live tv and recording is that I will want to burn recordings to dvd. Thus, that will increase the load on the cpu, won't it?
I might want to watch tv while it's doing this or watch a dvd on my other machine so the viewing is not interfering with dvd burning etc.
But, are people making do with less powerful machines?
I've never gotten a good feeling for how much DVD decode acceleration various flavors of cards have, and what Mpeg decoders will actually take advantage of the builtin acceleration. I have an ATI 9550 but I use the Nvidia Mpeg decoder because ATI/AMD doesn't give you the decoder unless you bought the card from them (I have an OEM card from Diamond).
Is there a standard for DVD acceleration under dx9 or dx7, or is it manufacturer dependent?