Cars are increasingly becoming computer controlled, but your only glimpse of all this digital power is likely to be a range estimation for the current petrol tank contents.

Most of your car’s computational ability is hidden behind the scenes. Aside from engine management, though, there’s a lot more functionality you can add to your vehicle by fitting a PC inside it.

Geek out your ride

Just as desktop PCs come in all shapes and sizes, there are many species of in-car PC. They can be hidden away in the boot, hog the glove compartment or go under the passenger seat like a stereo power amp.

You can even fit them in the space where the hi-fi would normally be. But two features they all have in common are the need for low power consumption (it could all be running off your vehicle’s 12V battery) and the limitation on space.

Fitting a glove compartment or boot PC is likely to be a fairly major work of car modification, but it does allow a slightly larger PC than dashboard installation.

If you want to put displays in headrests for rear passengers, installation is best left to those who install PCs in cars for a living, such as In-Car PC or InCarOffice.

However, for the less valiant modder, a PC that fits into an existing slot is the least painful option – although still in a league of difficulty far beyond building your own desktop.

In-car hardware

Considering that your in-car PC is likely to be expanding on the features of your car stereo, this is the most obvious location for the control interface. The DIN standard for car audio head units is ISO 7736.

This specifies a face panel of 180x50mm for a ‘Single DIN’ unit, and 180x100mm for ‘Double DIN’. In-car PC barebones are available conforming to either of these standards.

However, the ISO standard doesn’t specify a depth, so your chosen barebones may still not fit in your car. The only way to check is to measure the depth available and consult the vendor’s specifications, leaving plenty of room for cabling.

A larger PC will fit into a Double DIN box, but it will also be a little harder to install. Your car will probably only have a Single DIN car audio head unit installed, so adjacent space will need to be found.

Don’t expect to be able to buy any car PC and simply slip it in as you might a car stereo. Depending on your vehicle, you may need a different fascia panel and mounting kit, and to add amplification or conversion stages to the audio output.

What are the choices?

For a PC that isn’t located in the car stereo space, there will be also be plenty of cabling to perform. There are lots of options for the actual PC.

You can buy a chassis such as the VoomPC-2 and Mini-ITX VIA or Intel Mobile mainboard separately from the likes of www.cartft.com or www. kustompcs.co.uk.

Alternatively, a variety of barebones are available, such as the CALU-M Fanless or S631-C or HC. The HC version of the S631 is tall enough to accommodate a PCI slot riser, while the C version is around the size of a 5.25in optical drive.

Although a barebones will already come with many features integrated, including graphics, you will need a processor (in the case of Intel-based mainboards), memory, hard disk and optical drive.

You will also need to add an appropriate power supply which is capable of dealing with the wildly erratic DC supply from a car battery. However, the most expensive additional component will be the touchscreen, which will cost at least £200, plus more to mount.