Compatible for SLI? [Solved]

I have a Gtx 9800+ and was wondering if i could run SLI with a Gtx 560.

You could but why would you want to? Coolbits, the program for mixing cards in sli, will basically downclock (or was it lower the ram size) the better card. You're probably better off running the better gpu alone. 

Just think of it as Raid 0. You have one slow drive and one fast drive thats 2.5 times faster. If you put  them in raid 0 itll run slower, double the speed of  the slow drive so youre missing out on .5 times in speed. real world is different but should give you an idea. 

Oh, i didnt know how SLI really worked. thanks!