Questions regarding connecting Cablebox/TV to PC

[KJM]

Two questions, first off just condering if I can connect my DVR/Cable Box to my PC using Component cables or is getting a TV Tuner card and coaxial cable only way?

Second, I have my TV connected to my PC via HDTV cable, how do I get PC sound onto my TV (not using Computer speakers)

[WarEagleAU]

1st Question : I believe the tuner card or a variant thereof is the only way. TV OUt is a standard option, not tv in.

2nd Question: SPDIF (Sony Philips Digital InterFace) is the way to go for sound on your tv, or surround sound system.

[KJM]

2nd Question: SPDIF (Sony Philips Digital InterFace) is the way to go for sound on your tv, or surround sound system.

It seems to be to big for computer volume jack