Very powerful and cost effective for this sort of machine
I recently built an HTPC. The goal was to build something close to the size, performance, and quietness of the Mac Mini. Conventional wisdom about the "Apple tax" made me think I could do this for hundreds of dollars less than a Mac Mini.
As it turns out, my expectations were WAY off. A mini-ITX board with a low profile cooler is already basically the same size as a Mini, and that's before you add a drive and a power supply. I ended up going with one of the smallest mini-ITX cases on the market, the Antec ISK 110, and it's still about twice the volume of a Mini and that's not counting the external power brick it requires. Disappointing. And even using the cheapest available components on Newegg, it ended up costing over $300, and that's before the cost of Windows. I would have been happier just buying the Mini. It would have been roughly the same price for a superior computer.