How to Re-enable BIOS on PowerEdge PERC 5/E Adapter?

I have a Precision 390 to which I added a PERC 5/E adapter today.   It came up fine and I entered the BIOS.  Unfortunately, I de-selected the option to enable the BIOS.   From that moment on, I no longer see the adapter in the list of adapters during system startup.  Further, the adapter is now invisible to Windows XP and I cannot add the Dell Windows driver.    The SAS RAID storage utility also does not see it (although that is probably because of the missing driver).

HOW do I re-enable the system BIOS option on this adapter?  I have been through the user manual and it only tells you how to select it once the BIOS configuration tool is already running.