This may be a BIOS issue, I have a feeling the FR series a quite old systems (correct me if I'm wrong!). Try a BIOS update, bu be warned they CAN kill your computer should they fail - its very risky but check VAIO-Link for updates (link below).
Next try reseating the new RAM into the system, and then press F2 repeatedly to access BIOS, then press F9 to restore default settings. Press F10 to save and confirm exiting. The computer will reboot. Allow Windows to start, then check the Memory Reports in the System Properties window (press + + or click Start, Run then type in CONTROL.EXE SYSDM.CPL and press enter).
