SLI/CFX requires no changes to BIOS settings. First card goes in PCIX16/X8_1, second in PCIX16/X8_3. Make use of the EZ_Plug (ref p1-33) for multiple cards. I don't think there is anything else R5E ed10 specific for SLI/CFX setup.
"Before you criticize someone, you should walk a mile in their shoes. That way, when you criticize them, you're a mile away and you have their shoes." -- Unknown