If you're ready to install Win7 then back up anything you need from the hard drive and wipe it with Diskpart Clean Command from the booted installer's Command Line accessed by pressing Shift + F10 at first screen here:



Then close Command Box and click Install Now, do a Custom Install using Drive Options to partition and format as you wish or just click Next for installer to do it for you, follow these illustrated steps to Clean Install Windows 7.

If that fails check for newer BIOS version. If none reset the BIOs to defaults, while in BIOS setup set SATA controller to AHCI to try install, then IDE if necessary.

If that doesn't help then work through the hardware tests in Troubleshooting Steps for Windows 7