Inspiron 15R-Cannot get into BIOS Setup

15R-5521 laptop with InsydeH2O BIOS. Sytem boots to Win7 and runs ok, but cannot get into BIOS Setup. F2 during POST gives blank screen. F12 during POST gives menu, but selecting "Enter Setup" gives blank screen

Dell phone service troubleshooting steps.

(1) Removed battery and AC, held power key down for 30 sec, reinstalled battery and AC, F2 still gave blank screen.

(2) F10 at POST ran diagnostics, no errors shown.

(3) Reflashed BIOS from A10 to A12. Still same.

Service now advises to send in to depot for motherboard replacement. Is F2 at POST the ONLY way to get into the BIOS Setup. I would think that a utility would be avail to boot to from CD/USB to get into Setup. Any ideas ?

BTW at F12 menu, the boot type is set to "legacy" and secure boot is "OFF".