The HD is from my Dell (purchased in 2005). Quick specs I have are - "Hard Drive, 160GB, Serial ATA 7.2K, 8MB, NATIVE COMMAND QUEUEING..., Seagate."
What I purchased was this Western Digital Caviar Blue WD3200AAJS 320GB 7200 RPM 8MB Cache SATA 3.0Gb/s 3.5"
The new build will be a mixed use of home purposes and gaming; essentially a budget gaming system. The country is the US.