No boot Device Available and than Sata 1 Sata 2 ... Inspiron 580 (Late 2009)

A computer in my house was not fully starting up and said No boot Device Available and than Sata 1 Sata 2...

Anyways so i did a diagnosis test on it and right off the start it said the harddrive is not found or something along that line. So i opened the computer and made sure the wires were all good and i changed the wire port to another one and still it did not read it. Well so my conclusion was that the Harddrive is DONE! So i bought another one that is made for my computer and NOW here's the problem I get the same msg however when i did the diagnosis test the hardrive is readable now and i can even hear it but since its a NEW hardrive I am guessing there is no window on it right? or what? this is where i'm lost and i dont know what i am suppose to do now. 

What do i do from this point on? 
PLEASE HELP!

Inspiron 580 (Late 2009)