7 min read

Put A PC In Your Car

Computing hits the road with this mini-ITX system.
Assembling the Car PC

Before assembly, and before making final decisions on parts, make sure you have a solid plan and a proper place to work. Finding the right place to work on your car PC will make for a cleaner installation and speed your project along. Look for a protected location with good lighting. You'll also want to use a droplight to help you with interior fitting and for working under the hood. Don't forget Internet access for downloading applications, updates, etc. While garages with a high-speed hook-up might be hard to come by, you'll only need network access for a short period. So be prepared to string a long cable, or use a USB wireless-network adaptor.

No special tools are needed to build and install a Car PC. You can go with the favorite tools of professional installers, such as good wire strippers with spring action and wire-gauge sensing; a heavy-duty crimping tool; a thread-locker compound such as LocTite, which can prevent screws from coming loose from repeated vibration; and a collection of faston and other wire-splicing parts. Wire connectors are available in various assortments or in bubble packs from auto-supply stores, and they are highly recommended for a safe and professional-looking installation.

Here are the 14 steps for the Car PC assembly:

CarPC Assembly Steps


Install memory and configure VIA mainboard ___
2 Install the motherboard on the base plate of enclosure using four screws.

See illustration of parts layout above.

3 Install the 2.5-inch hard drive using the four silicone rubber shock absorbent pads over the hard drive mounting holes. Fasten the hard drive using four undercut M3 screws attached from the bottom. (See illustration of parts layout, above). Shock pads for mounting the hard drive are included with the VoomPC enclosure ___
4 Attach a 44-40 pin IDE cable to the hard drive and motherboard. ___
5 Attach the M2 ATX power supply over the hard drive, using the remaining standoffs. See illustration of parts layout above. ___
6 Connect the ATX cable harness (provided with power supply) to the motherboard. Use small tie-wraps to manage the ATX cable harness. This is important, not only to prevent rattle and cable wear, but to improve air-flow critical for proper cooling. Note: If you are using a different VIA mainboard, you may be able to eliminate the ATX cable harness entirely, by a custom ATX power extender bus made for use with some EPIA MII mainboards (available from ) ___
7 Connect the Red / Black / White (terminated in faston quick-splice connectors) to the power supply. Red is un-switched battery, white is switched battery (ignition) and Black is GND. When looking for a power connection in, remember that the switched battery (ignition) is usually present on your cigarette lighter or most of your 12-volt power wires. Un-switched battery (harder to find) is present on your alarm system or other 'always-on' electronics. Use a volt-meter to detect switched versus un-switched wires. If hard to find, connect directly to the battery. ___
8 Connect the LED wire to the LED output if you're the M2-ATX for LED pins. ___
9 Connect the ON/OFF wire harness (provided in the PSU package) to the M2-ATX ON/OFF controller and to the ON/OFF mainboard switch. ___
10  (Optional) Attach your audio amp See details in VoomPC enclosure manual to connect the Amp Enable wire harness to your amp. Please pay special attention to the polarity of the wires. Note: Your amplifier remote control unit actually needs only one wire (RMT), GND is optional. ___
11 Hook up display, keyboard, etc, and perform a quick test of your system by turning ignition ON ___
12 Attach temporary CD-ROM drive to load operating system and application software. ___
13 Secure the enclosure in the vehicle using the four front/back mounting screws. If you don't want to drill holes into your car chassis, large velcro pads work well when attached to the bottom plate of the enclosure. Use the "hook" side of the velcro pad on the PC to attach to your car's carpet. This works very well in most interiors. ___
14 Locate and mount touch screen. For many applications, this can represent a bulk of the work and require patience. Work slowly and carefully knowing that a slip of the Exacto knife or spilling adhesive will mean a trip to scrap yard or a costly trip to the dealer's parts department to fix. ___

Here's a photograph showing how the components are placed for assembly onto the bottom plate of a VoomPC case. Note the overlapping strata of parts to retain our small footprint:

A Word about Car PC and Safety

Using a PC on the road requires a tremendous amount of responsibility. The purpose of having a car PC—in addition to being really cool, of course—is to add to the enjoyment and safety of the driving experience. Unfortunately, having something as wonderful and complex as a computer within sight and reach of a driver can present a serious distraction.

In other words, don't make your in-car PC a driving hazard for yourself or your clients. Instead, follow these important steps as part of your installation:

  • Consult your local laws. In the U.S., for example, many states restrict the use of an in-car video monitor that's in the view of the driver.
  • Take extra care to provide a safe installation. Design application access to be as easy and hands-free as possible.
  • Consider having a serious talk with your clients about the safe use of the car PC. Since everyone will have questions and want to talk about their car PC, suggest an explanation before the trip gets underway. Or suggest offering to pull over to give a complete tour of the hardware and applications curbside, rather than while in motion.

Once the Car PC is built and installed, you'll be ready to load the applications your client desires. But be prepared for questions, lots of them. Car PCs get loads of attention from both potential clients and passers-by. Don't forget to mention to your potential clients that having a Car PC consolidates all their miscellaneous hardware and wires into one box with a large, easy-to-use touch screen. It also lets them run their favorite PC applications in their car. PC gamers will love it for the novelty. Salespeople will love the GPS and the integrated phone and PC applications. And all your on-the-road clients will enjoy the superior media ability of motoring in style with their car PC.

SIDEBAR: Additional Resources for Building Car PCs

Online Vendors: You'll want to source your parts from people who are familiar with the mini-ITX and know the car PC business. I found these three online vendors to be among the best:

Discussion Forums: Check out the many car-PC sites forums for tips and tricks. Here are three I like:

Books: I recommend two helpful books devoted to car PCs. These two books can be especially helpful if you don't have a lot of experience with 12-volt DC systems, are unfamiliar with "faston" connectors for splicing wire quickly, or are uncomfortable cutting into ignition wiring:

Additional ideas: Have a look at some pre-built car PCs. Streetdeck is one that has attracted a lot of attention.

General information on mini-ITX systems: Check out the EPIACenter.

ANDY MCDONOUGH is a professional musician, composer, voice actor, engineer, and educator happily freelancing in New Jersey.