Delete all partitions during booted install and create one new one to format using Custom install>Drive Options as shown in
Clean Install Windows 7 , or just click next and the installer will do it for you and begin install.

If this fails then first wipe the HD with
Diskpart Clean Command accessing the installer's Command Line via
DISKPART At PC Startup .
If this fails, reset the BIOS to defaults. Set SATA controller to AHCI mode.
Clear CMOS - 3 Ways to Clear the CMOS - Reset BIOS
Unplug all other HD's and peripherals.
More tips here to get a perfect
Clean Reinstall - Factory OEM Windows 7 . Did Windows 7 originally come with the laptop, as you should then use the Product Key on COA sticker which you own for the life of the laptop to reinstall as often as you please, not waste another expensive Ultimate license.
If not, how do you plan to activate Ultimate?