The last PC that I built was a Shuttle mobo with an AMD 2500XP+ overclocked (a very popular combination for overclocking).
The PC has been rock solid but it's time for an upgrade. I think my current game box will be relegated to a VMWare Server of some sort. Since it has IDE storage I'm going to install the OS on the ide drive and then use the iSCSI appliance as I covered in this post to provide a VMFS-3 capable partition. I'll be sure to document that process when the time comes.