If you have new ATI graphics chip you would be able to send audio through HDMI from your PC, but even if you can I don't think your TV will be able to send more than two channel (audio signal) through SPDIF.
Best connection without purchasing video and/or audio card is to use VGA and use analog signal to Samsung HT-DL1000 Then use RCA to send audio from Samsung to TV.
You can't use HDMI without proper hardware. Not DVI to HDMI.
I have an Asus P5Q, but im going to connect the TV to the graphicscard. I have a Club3D HD4870 which has a built-in audio unit. So it can send both video and 7 channel audio.
The TV im getting isnt even released yet, it will become available for purchase this weekend, so i cant check out the manual yet. But i guess it will be able to send multichannel sound. I dont think a TV this new will be able to send 2 channel only.
I suggest you call the manufacturer and ask tech-support before purchasing to avoid disappointment, or at least you know what you're getting into. You'ld be surprise about manufacturers misleading or intentionally limited advertisment.
A couple of things. First, your TV will probably pass through only 2 channels of sound from your computer to your home theater receiver. For example, if you are watching a movie on your computer via PowerDVD or something like that, it could output 2 ch LPCM and Dolby 5.1 over HDMI, but your TV will probably only be able to handle 2 channels and strip all the other data out. Thus the digital output from the TV will not give will your home theater stereo but not surround sound. This was a problem I had when I set up my HTCP.
Depending on your motherboard there may be another solution. Is your PC a home-built one or a mass market? If home built, what make/model is your motherboard. If mass market what brand/model. The reason I ask is a fair number of motherboards have an s/pdif (which is toslink/digital coax) header even if they don't have an output out back. My motherboard, a mATX Biostar, is one such motherboard. If you have this then you can cheaply make a riser card to output toslink straight to your receiver. You would then use HDMI for video and toslink to the receiver for audio. Vista does not, however, allow for two audio streams at the same time (for copyright protection AFAIK) so you can't use both at audio outputs simultaneously.
The last option, and the easiest, is to get a sound card.
Another plausible solution i came up with is just buying some el-cheapo secondary sounnd card like Trust or Sweex or something. Since spdif is a digital signal which is just 1's and 0's, not much can go wrong there.
Ofcourse i'd have to manually switch sound-output in windows, but that is np at all.
Ok, that motherboard has the necessary header. Page 2-32 paragraph 11 of the user manual. It also appears that Asus sells the very device I was suggesting that you could build. So, if you can find someone selling the Asus riser, you could go that route, or if you are a DIY type, you could make your own.
The other problem I now see is, where are you getting the HDMI from. If you are using a video card and an DVI/HDMI converter, you won't have audio. Some video cards will output audio, but they will often connect to the spdif header that I have been talking about. This means that you may not be able to have audio via HDMI at all if you use the spdif header for a toslink to the receiver.
Hooray! Received my TV yesterday and hooked it up this morning by connecting it with HDMI to my PC and TOSLINK from the TV to my home theatre. Downloaded Valkyrie (1080p) and guess what. Actual 5.1 surround =D