What kind of computer is this? Home built or name brand?
What are the complete system specs? List the parts by brand and model including the power supply.
What kind of hard drive is it? IDE or SATA?
If IDE, is it jumpered properly for the type of IDE cable you're using?
If SATA, which SATA port do you have it plugged into?
Is the hard drive recognized by the BIOS?
Cricket