Hi,
If the BIOS version is same as vendor website, still you need to update it(if possible). Reset all the BIOS settings to DEFAULT factory settings. Enable the APIC from BIOS which is must for Windows 7. There will be two entries with the similar names APIC or ACPI ( you need to change APIC). Remove all of the external storage and USB devices.
Once all changes done save it and reboot the machine. Start the setup from setup disc, remove all the partitions from the system and create a single partition ( C: ) - only if no important data to keep as backup. Formatting will be taken place while installation begins.
Give a try and let me know.