I'm interesting in putting a Car PC into my 05 Kia Sportage. (I think it has a double Din radio in it so I think it would look perfectly).
I was wondering if anybody had built or installed a Car PC before? I have a couple of questions about it.

1. How does the GPS work? Is the GPS built into the computer or is it some antanna ? My car has a spot for GPS, but wasn't part of the car. I just wasn't sure if I could install the GPS thing in a different location?

2. Most that I have seen have onboard sound. Is this good enough for a car stereo? (I just have all stock speakers and so forth).

3. Is there an HD Radio card that I can put into a computer? Is there a Radio card that gets FM and AM stations?

4. How are DVD's played on these systems. I see them all have a DVD option, but i don't get how the DVD is put into the computer. More I'm wondering if I have the computer installed behind the dash, is there a way I can access the DVD drive from my dash board (somewhere by the touch screen).

If you know anybody that can answer one or any of these questions it would help a ton.

GPS needs an antennae and a receiver. The car likely has an input for the data if you have a multi-display or something.

You can put the GPS where you want, but the question is where it is displayed.
for the antennae you want it in the most visible from orbit spot, because the more hidden and buried it is, the longer it will take to acquire signals from the satellites.

Most onboard/mobo audio would be more than fine for car audio (since fidelity is lost in such a noisey environment) where you're not going to be picking out the 3rd viola in a concerto.

I don't know of HD radio and computers never used it myself, but I am certain there are some just because if it can be done someone is trying to slap it together whether it works or not is another question.

AM radio on the other hand is an issue, AM and most electronics don't work, computers especially cause AM radio to freak out and be full of static and high pitch sounds. Most tuners are FM only, although TV audio would be fine.

For the DVD I would suggest a 2 part USB solution;
A) a DVD-changer in the trunk, under the seat, etc.
B) a single slot DVD drive you can swap your media in/out with. Mount that however you'd like.

The main issue will be having a large enough buffer so it won't skip, professional setups have Gforce absorbing assemblies with floating suspension to absorb road shocks, but barring such a setup a large buffer would help, but I have a feeling that if you go over any noticeable bumps you're going to have problems. It's almost better to get a large laptop drive and then pre-load your DVDs instead.

Best way to reduce shocks is to have a fixed path suspension mechanism that absorbs shocks but doesn't get thrown around much. Not sure if you can get one with a USB interface though.

Many people have done this, including a friend of mine I helped for his bronco (HDD only no optical), so you might learn alot from their experiences.

http://www.argyrides.eu/bmw/mods/carputer/carputer.htm