GTX 275 sli issue

Hey I purchased a EVGA GTX 275 1786 MB card a couple of weeks ago and I traded in my old 9800GTX for a EVGA GTX 275 896 MB card. When I turn on my computer and go to NVIDIA control panel there's no option for SLI at all. I tried reinstalling the drivers and I switched the two cards positions and still nothing. My system is Vista 64bit, 8GB DDR2, 500GB HD, 750W PSU, Intel Core 2 Quad, 2 GTX 275 (896MB, 1789MB). I read that on the SLI faq that the card with the higher memory will cut it's memory in half to work correctly with the lower memory one but that doesn't seem to be the case with mine. Any help would be appreciated

I fixed the issue. I had to install coolbits and modify the value to 18.