This is a PC I used throughout university, and have been using it for gaming for the past year or so. I do software development for a living and needed to move to a 64bit system.
motherboard: Asus P4P800-E Deluxe (onboard 5.1 sound, gigabit network)
processor: Intel Pentium 4 3.0Ghz
video card: NVIDIA 7600GT AGP
1GB dual channel Kingston PC3200 RAM
Hard drive: SEAGATE Barracuda 7200 rpm 320GB SATA (that is the newer 7200.10 drive)
optical drive: HP Branded 52x CDRW
power supply: Antec smartpower 450W
case: silver case with clear window side panel with fan on the window, and back.
Everything was bought new and used in a nonsmoking house. The hardware is rock solid, and as far as gaming goes it's still very capable. I just recently finished playing fallout 3 on it, and play TF2 constantly on it with high video quality settings.
asking price: $400 O.B.O
I determined the price by just taking the average price of each component on ebay and adding it up.
PM me if you are interested