IF YOU WANT to build a small yet competent PC then Thin Mini-ITX is the way to go, and here's a guide on how to build your own from start to finish.
To start you'll need to select a motherboard to use, since the entire system revolves around this component. Mini-ITX boards are small at just 170x170mm and normally have a height of around 44mm. Thin Mini-ITX cuts the height down to just 25mm so these are even more compact.
We've selected Intel's DH61AG for our system, which uses the LGA1155 socket and the H61 chipset. It supports the latest Intel Sandy Bridge processors up to the Core i7. One thing to note is that it only accepts chips with a thermal design power (TDP) rating of up 65W so you can't whack the fastest Core i7 in it, which is rated at 95W TDP.
Although it's small the board has a long list of features including two DDR3 SO-DIMM RAM slots for up to 16GB of memory, two SATA ports, a full size mini-PCI Express slot, a half size mini-PCI Express slot and one PCI Express 2.0 x4 slot.
External connections on the rear of the board consist of an external power connector, two USB 3.0 ports, two fast charge USB 2.0 ports, a DVI port, an HDMI port, an e-SATA connector, an Ethernet connector, and microphone and headphone ports. For the comprehensive list of specifications for the motherboard take a look at Intel's specifications web page.
For a processor, we opted for the Sandy Bridge Core i5-2405S, which runs at 2.5GHz and has Intel HD3000 integrated graphics on-die. We chose this one because it's the only 65W chip to have the latest graphics core, rather than the older HD2000 revision. With Intel's Turbo Boost 2.0 technology the chip we selected can reach a maximum of 3.3GHz.
You might want to opt for the higher clock speed of a Core i5-2500S at 2.7GHz or a Core i7-2600S at 2.8GHz if you're going to use a dedicated graphics card in your system.