My understanding of the new SLI since it doesnt work like voodoo's sli is that a game profile is needed in the driver for it to work and there is currently no profile for Everquest II. Do a search on the EQ2 forums and you'll see some unhappy people.
UPDATE: I just did some searches again and it looks like the Forceware 71.40 Driver will enable SLI for EQ2 now.
http://eqiiforums.station.sony.com/e...ght=sli#M52369
You can get that beta driver from places like
www.guru3d.com