For an HTPC...

[jonessoda]

If I want to build a Home Theater PC and use it as a DVR, how much hard drive space should I have (yeah, yeah... as much as I can afford, right?)? How much recording time would I get off of 1 TB dedicated to DVR (as in, programs and OS go on another HDD, the 1TB is solely for recording)?

How about RAM? Will a gig be sufficient, or should I go for 2?

I assume I need a TV tuner. Any suggestions on a particular one?

 

[Lord Evermore]

Using a Hauppage PVR150 and recording straight to MPEG2 at a good quality, an hour of standard TV takes up about 3.5GB, leaving me with 72 hours of video on a 250GB drive. If I were to recompress the video to Divx or WMV that could be quadrupled. A terabyte of storage space is going to be more than enough unless you plan on saving everything you ever record, forever. Personally I save very little beyond the time it takes me to watch it, I'm not using the PVR as an archive, just to watch TV when I can actually be there to watch it rather than on a schedule. 250GB is enough space that I can go on vacation for a week and not run out of space, and not even have to recompress the video.

HDTV of course will result in more space being taken up.

A gigabyte of memory is very sufficient in most cases. Mine uses only 512MB, running on an AthlonXP 2100+. Actual memory use with BeyondTV is only 350MB or so.

There are lots of forums dedicated to do-it-yourself PVRs, you should look into those.