Laptop won't POST

[davisd2000]

Just built out a barebones asus Z62F, and it won't POST. Where do I start with trouble shooting? I'm a newbie at this kind of thing.

 

[davisd2000]

good advice. i dropped it off at a shop and they diagnosed a nonworking HD which leads to a followup ques: I simply plugged in a 2.5" hard drive SAMSUNG 160GB HM160HC 5400 IDE ATA 100, but 4 pins are left hanging, ie I have a 44 pin HD going into a 40 pin connector.
Do I need another cable to go into these last 4 pins? Or possibly a jumper between them?