How are you reformatting your PC? Are you doing a Factory Default Image? [which reformats your PC to its original state as when you bought it new, this process is pretty much user independent, i mean you don't have anything else to do after click on this option.]
if so, look online or in your manual how to access to this menu is either by pressing
F2,F5 or F8 depending on the brand. also you don't need any CD installation, everything is in the partitioned section of the hard drive.
keep us informed, good luck