sli overclocking question

Hey i have two 8800gt oc video cards in sli, does anyone know why only one card overclocks?i am using expert tool right now which works for one card!but for the second card i don't think its overclocking because the temps are different by a fair margin,one card is hot to the touch but the other card isn't,i have used other overclocking tools to try and fix it as well,any suggestions would be great.

if indeed only one card is being overclocked, sli is disabled, i had this problem, download GPU-Z and see if both are on the same frequency, it also tells if sli is enabled, and your temps, but this isnt an overclocking tool, use ntune for overclocking your sli set up, but beware, i ran two 8600GT's and one card couldn't handle the overclock, and the one did, second card fried and i went back to just one card, but now i run a 9800 GT and will never overclock my graphics again, im going to stick to ocing my cpu and that's it