Does anyone know if there are any options in the Dell BIOS (PowerEdge R610) for disabling the 32-bit compatibility mode?

Background: A PCI device in my system requires a large memory (>2GB) and BIOS fails to output anything to the screen in this mode. I'm not sure why the BIOS is hung as there is not serial port output either. I'm speculating that the BIOS is unable to fit this 2GB PCI window below the 4GB limit and is hung. I'm assuming that if there is anyway to tell BIOS not to worry about being compatible with a 32-bit OS, then it will be able to allocate the requested large PCI memory. Any suggestions?

thanks,

-SP