This is almost always an installer error. Where did you get Windows 7? Check HASH or download another ISO, burn to DVD or write to flash stick using
Windows 7 USB-DVD Download Tool.
Boot installer using one-time BIOS Boot Menu key given on first boot screen. Unplug all other HD's and peripherals.
If this fails, wipe the HD first with
Diskpart Clean Command accessing
DISKPART At PC Startup.
Next reset BIOS to defaults in BIOS setup, set SATA controller to AHCI to try install.
Next test your HD using maker's
HD Diagnostic extended CD scan, then test your
RAM - Test with Memtest86+ for 5-6 passes. Remove all but 2gb RAM to try install, then swap RAM.