Well, I just got this gaming pc today. The owner assured that it worked and was ready to go, it just needed the OS.
I tried installing a copy of Windows XP Pro and it loads up the disc but when it gets to the part where it saves stuff to the hard disk/drive, I get a message saying that the Hard Disk isn't detected/isn't on.
I already opened up the case and I can see that the hard drive is there and it looks like it's connected properly but it doesn't seem to detect it. Any help? I'm new at this stuff so I really don't know what to do here.

Some info on the pc:
CPU: Pentium "D" Dual Core 3.2 GHz CPU
Gigabyte GA-965P-S3 Motherboard
Graphics Card: x1950xtx w/512MB GDDR4
2GB (2048 MB) DDR2 Main Memory
300 GB 7200 rpm SATA Hard Drive
Pioneer DVD/CD Burner Drive
3.5" FDD
500 Watt Power Supply

You need to load the SATA drivers at the F6 prompt from XP.

The drivers are on the motherboard CD and need to be copied to a floppy disk.

The F6 prompt comes up right away when you boot the XP CD.

Ah, well I got it working now, thanks for the reply Jephree!

No problem. Let us know if we can help further in the future.