The last computer I built was to be my home's main media center PC. I was focusing on the audio and video capabilities, but also strongly trying to keep my cost down. After speaking to a friend, I decided to go with a Gigabyte AM2/AM3 motherboard that had integrated HDMI for simple connection to my home theater system. In deciding on a processor, went with the AMD Phenom X3 8550 for it's cost and processing power. Picked up 4GB of DDR2 RAM, too. I was able to find a 640GB Western Digital Black SATA hard drive with bundle pricing together with the case, so that was a simple choice. The case I chose included a 585 watt power supply and got excellent reviews, so that's what I used to hold it all together.
Putting the system together was fairly straightforward, with little complications. The case, due to the nature of low cost, was of pretty low quality - material wise. Removing one of the expansion slot covers from the back caused me to bend the entire rear, which I quickly repaired. Installation of the motherboard and processor went very smoothly, however. RAM installation was a breeze, and connecting all the cables was no problem at all. After mounting the hard and optical drives (which I already owned,) I installed my TV tuner card and zip tied all the cables for a neat installation. Professional-looking quality, if I must say so.
Powering the system on for the first time was somewhat of a challenge. In going through the documentation, I read that I had to enable the on board HDMI port before use. This wasn't necessarily a problem with assembly of the PC itself, but required me to hook it up to a standalone VGA compatible display. Afterwords, however, I was able to use my home theater system for the display, and began installation of the operating system. Because this was to be a media center PC, I opted to go with Windows 7 Home Premium, and that installation went silky smooth. No hangups whatsoever. Due to the large quantity of drivers that Windows 7 included, I didn't need to do any additional loading of drivers once it brought my desktop up for the first time. I did, however, need to load the utilities for the integrated gigabit network controller and also for my wireless media center keyboard / mouse combo.
Overall, the experience of building my new home theater PC was one of the simplest computer building projects I've ever taken on.