How do I format my NEW WD HDD for my iMac?
How do I format my new 1.5TB WD HDD so my iMac see's it?
Model A1225 / Early 2009 / 2.66, 2.93, or 3.06 GHz Core 2 Duo processor
If you've already installed the new hard drive, start up from your system installation disk by inserting the disk and restarting holding down the "C" key. Go to the second screen pull down menu to Utilities -> Disk Utility. Now format the drive. Next quit disk utility and continue with the system installation.