Best soundcard if have outboard DAC

Looking to use a PC as a transport. Will have an outboard DAC feeding a preamp. I want the soundcard to feed the DAC with a digital signal. I don't want the PC/soundcard doing any processing, only sending the untainted digital signal to the DAC. Sound is important, not cost. What is the best soundcard for this? Also, what is best: AES/toslink/USB?
You can use the Cmedia 8738 based sound card to output the 44.1 signal to the DAC. About 10.00 dollars at the store.
If you've got an outboard DAC and the USB to get to it, as far as I understand it, you're bypassing the onboard soundcard entirely -- so it shouldn't matter what it is (or whether you have one at all). Perhaps I'm missing something, but why not just skip it?

Guess it depends on the DAC. Recently bought a Headroom Total Bithead simply because it sounded like a cool idea. It's an outboard DAC / Headphone amp designed to run off of a computer USB port. It's totally plug and play -- plug it in and it configures itself to run as the default sound card as long as it's plugged in -- thus bypassing the onboard card. I'd previously been using the DAC on my card (which is a decent soundcard) and then running analog into an outboard headphone amp (an older Headroom), but the sound was pretty mediocre. Running USB direct to the Bithead is a lot better -- hardly perfect, but definitely a huge improvement. Perhaps not what you're looking for, but the concept (bypassing the onboard card alltoghether) sounds like the way to go to me....
You need to bypass the Kmixer in a windows based OS. Kmixer upsamples to 48khz, this is a no-no. It does not matter that you use onboard sound or any other device as long as the output is bit perfect. Hence the $10.00 dollar Cmedia solution will output a 44.1khz bit perfect signal to the DAC.

This has been researched extensively by others and myself. I am runing Foobar2K with bit perfect output to my Music Fidelity Tri-Vista 21 DAC. Hope thhis explains it clearly and to the point.
Thanks for the great responses.

Racerxnet: That sounds like the way to go. I use Cinemar MainLobby, which is a front end for J. River MediaCenter. I believe J. River has something like bit perfect output (it has bit perfect ripping).

What kind of connection do you use to the DAC?
I am using a toslink connection due to the distance to the DAC. About 20ft. The PC outputs to the overhead projector and hence the distance involved. There is no signal loss or interference with this setup. Sounds great to me. I am using the PC as a HTPC front end / data Base. Here are the components.

KT 800 AMD PC - WinXP Pro
Electrohome 8500 CRT Projector Via PC output
Music Fidelity Tri Vista 21 DAC
Bryston BP 25 Pre Amp
Infinity Crossover
4 Bryston 7BST monobock amps
Infinity RS1B speakers.
If you must use an internal card (not the best solution), then I believe the Lynx is the best around.
When feeding to an external DAC, the sound card only needs to be bit perfect. The DAC does not care about brand names if the output is SPDIF 44.1khz. Redbook standard!!
So, Let me see...

I think I am wanting to go digital out from my PC because I have read and been told that the DAC onboard my Kenwood receiver would be better then any soundcard DAC because of the noise inside the PC etc. First question: Would the DAC onboard a highend receiver indeed be better then the DAC on an external chip? It is a Burr Brown DAC.

Second question: If I am going to rely upon the DAC onboard my receiver, I am relying on a digital SPDIF connection; either optical or coaxial... which is better?

Third question: Is there a difference in quality between different digital outs? Is the sound quality from all 24bit digital outs the same or is there differences? Is the difference in the software or hardware manipulation of the sound before it goes digitally out?

These questions are helping me determine if I need X-Fi, or a lesser card that has SPDIF out? I want to know what the differences are if I am not relying on the analog outs (receiver instead of PC speaker).
I would recommend skipping the soundcard--get a USB audio output device like the Waveterminal U24 that will output spdif. Other cheaper alternatives include the Edirol UA-1D or the M-Audio Sonica. If you use USB instead of coax or optical, it sounds better for longer runs. You will still need a short coax or optical to connect to your receiver (the general consensus seems to be that coax is better, but there are some situations where people claim the optical is superior--you would have to try it).
Are all digital outs (USB or otherwise) thet produce 24bit the same quality? Would something like the new Creative X-Fi give me a better quality digital out then one of the externals that you recommended, or all they all the same?

Sorry, don't know much about things at this level...
Try both connections to the outboard reciever and let your ears determine what sounds best to you! It still does not matter what you use to feed the bits to the DAC. USB or sound card will not matter in the digital realm with 44.1khz output. Most Creative cards will not output 44.1 SPDIF. The Burr Brown DAC is a excellent D/A converter. Bits is Bits no matter what you use. The DAC is where the sound quality comes into play.
A lot of computer devices output at 48 kHz, not the native 44.1 kHz for ripped CDs. I know the waveterminal outputs 44.1. Bits are bits, but certain device may be more prone to jitter problems if they have lousy cheapo clocks in them.
"Bits is Bits no matter what you use."
I'm a little confused by this. Is jitter no longer an issue when the data source is a PC hard drive?
How do you guys bypass the Kmixer in Windows?? I use both my on board Nvidia sound card (optical out) as well as a Maudio 2496 (coax).

Unless I play DD or DTS, I am always able to change the volume with Windows meaning that the signal gets converted somehow. I use digital out but since Windows acts like a preamp I'm really not getting any benefit from using a external dac.

I'm using foobar 2k for music playback.

Any help would be greatly appreciated.

Kernel Streaming or ASIO works without Kmixer.
thanks, do I need some extra software to enable these two or are they soundcard options. I tried enabling ASIO on my M Audio soundcard but the Windows volume still worked.

Where do I enable Kernel streaming, is it from foobar? I really lack computer literacy when it comes to PC music but I hate having to change cds every 5 mins so a jukebox is the only way to go.