This is my current box. I bought it a few years back to replace my Athlon800. My main gripe at that point was noise, not so much the performance. The machine got designed to make very little noise, i.e. I selected a low-TDP CPU (for the time), isolated case, passively-cooled graphics card etc. It started out with 1GB of RAM, got upgraded to 5GB RAM.

Also, disk space got quickly upgraded from 400GB to 900GB. Except for some ventilator that's somewhat used, the box remains very silent. I finally decided to get 3x 2TB disks for a software-RAID5 configuration, i.e. sufficient (for now) storage. While being at it, I also got a 40GB solid state disk to put the OS files on - which makes for insanely quick boot times, as well as very quick program startups.

I use this box as my main desktop, but also fileserver for the LAN, and run several virtual machines for different services - among which, this website.