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A car computer (carputer) is an awesome system to install in your car. Not only can a carputer play music and videos, but you can also install navigation software, browse the web, download files, or do anything the PC you're using can do. However, many people don't know where to start, or they don't have the first clue as to what a carputer system consists of.

Here are some general tips and suggestions to get you started on your build.

Most people choose a mini-ITX form factor motherboard. Mini-ITX motherboards come in lots of different configurations; there are some boards for Intel, some for AMD, and some are VIA based. Some boards can handle up to Core 2 Quad core CPU's, but expect to pay mucho $$$ if you want that level of performance.

Popular choices are the VIA C3 and C7 mini-ITX based motherboards, but they are being phased out by the growing popularity of the Intel Atom boards. Intel Atom processors are widely used in netbooks, but their low power requirements and low heat build up make them perfect candidates for carputer usage.

A very popular, best bang for your buck motherboard would be the Intel D945GCLF2, in my opinion. Also, at less than $100 for both the CPU and motherboard, the deal is too good to pass up.

Power Supply:

The easiest, headache free solution is to use an intelligent DC-DC power supply. Intelligent power supplies have integrated startup/shutdown controllers that can sense and power your computer when you turn your car on/off. See how that can get annoying?

This includes, at the bare minimum, a power wire, ground wire, and a remote wire. The remote wire is wired to a 12v source that only becomes active when your key is in the ignition. The most common usage is to use the remote wire from your CD player/head unit, that way, when the CD player turns on, so does the carputer.

As far as brands go, I would go with Opus. While they are a little more expensive than the M2/M3/M4 ATX power supplies, they are of higher quality. I had an older M2 ATX that would only put out 10.9 - 11.4 volts on the 12v rail (not good!). Since then, I replaced it with an Opus 120w and it's been running strong since 2006. I would use a Pico PSU if you're extremely cramped for space, like in a glove box build.

Hard Drive and Optical Drive:

2.5" notebook hard drives are the most popular because they are small, use little power, and are rugged. I've been using an old 2.5" 80GB IDE for at least 3 years now. I've dropped the hard drive multiple times and have it mounted pretty badly, but it's still running strong! 3.5" hard drives need much more power, and power is precious when we're talking about small, 90-120 watt power supplies.

Optical drives; who uses optical drives anymore? The only time I used an optical drive was for the initial operating system install. Even still, you could probably get away with installing your OS from a USB flash drive. As for daily use, I guarantee an optical drive would receive almost zero usage. The only thing I can see an optical drive being useful for is to watch DVDs. If you're driving, do you really think it's a good idea to watch a movie on the way to work? If you're stopped, wouldn't you rather watch the DVD on your big screen in the house? At this point in our technological evolution, optical drives are becoming more and more of a novelty.

I have 1GB in my carputer and it runs pretty quickly on a full Windows XP install (I'll get to this later). 2GB would be even better, but it's not really necessary and I doubt you'll see a speed increase.

Enclosure/Case:

Despite what you may hear or think, a case is completely optional as long as you have your components mounted somewhat securely (meaning they won't bounce around like crazy while driving). Mini-ITX cases do exist and can be found at stores like Mini-box, MP3car, and Newegg. If you have the space, a slightly larger (but cheaper) micro-ATX case could be used instead.

I've been running my setups in the glovebox like this for over three years with zero failures. The CPU temperature settles at around 50-60c depending on the outside temperature. The hard drive is mounted to top of the glove compartment using double sided adhesive. The motherboard and power supply simply sit on a peice of cardboard.

Operating System:

My advice is to run a full version of Windows XP instead of a "custom" XP build such as TinyXP. Drivers are stripped out, services are missing, and in my experience, it's not the most stable OS either. Do you really want perform advanced troubleshooting for some odd program you want to work? Save yourself the headache and install a full version of Windows XP. Even on just 1GB of memory (2GB seems to be the standard now), XP runs silky smooth.

Then we come to the issue of whether to fully shutdown the computer or to have it hibernate when you turn off the car. Hibernation basically takes all the information present and stores it on the hard drive when the computer is turned off. Then, when the computer is turned on again, the data is restored from the hard drive and you're back to exactly where you were before you turned the car off. As nice as hibernation sounds, it's not very reliable in my experience. So, do yourself a favor and fully startup/shutdown for every session. A carputer on a full install of Windows XP doesn't take long to boot anyways, plus, it saves you a whole lot of headache in the future.

Front End:

Using a front end is completely up to you. The front end is basically a finger friendly program which contains all your media controls, media player, etc. It pretty much makes your carputer look like an Alpine or Pioneer double DIN touchscreen unit. Both are great players, but both have their negatives.

Road Runner is open source (free), but is a pain to setup correctly, and in my opinion, is too cluttered and doesn't look as good as Centrafuse. Centrafuse, however, is not free, but it's extremely easy to setup and works great right out of the box.