Every since i installed SL on my macpro 1,1, The fan on my 3870 has been going crazy, like full speed. I think its causing alot of heat which is causing the other fans to kick up to. Im thinking about just replacing it with a 4870 1gb flashed card but kinda don't want to. I just want the fan to act like it did in leopard. I tried to replace the kexts from Leopard which caused a lockout of my system. i had to put in my old 7300. Anyone has any fix's or idea's how to solve this problem? Kinda messed up apple wrote drivers that messed up my card.