This is most commonly a bad burn. Use ImgBurn at 4x speed with Verify. Make sure the ISO says "Bootable" in text at left when loaded.
Next make sure you have the latest BIOS version update, installed from Windows preferably.
If no later BIOS version, clear your CMOS: Clear CMOS - 3 Ways to Clear the CMOS - Reset BIOS
Check also in BIOS setup what your SATA controller setting is: Try AHCI first, then IDE if necc.
Wipe the HD to get a cleaner slate: http://www.sevenforums.com/tutorials...tallation.html
In rare cases you may need to insert your SATA controller at "Load Drivers" prompt during install. Unzip to stick or CD to load. Clean Install Windows 7 Clean Install with a Upgrade Windows 7 Version