Firecat is correct. If you bought a Windows 7 disc it is "Bootable". You have to put the Win7 DVD in the DVD drive. If it starts up and does not go to the W7 boot disk then hit the F10 key / Delete key, whatever gets you into your BIOS and you must set the boot order so that the DVD is listed before the harddrive. Save and exit the BIOS. Until you have the BIOS set properly and the W7 bootable DVD in the drive it won't work. Once it is set properly W7 will install from the DVD.