First, thanks for checking out my question. I have a 2.10 ghz core duo 2008 macbook "pyrn/santa rosa" I'm trying to fix for a friend. It has the original hd and 1gb of original ram. The o/s is a clean install of 10.6.4 OSX. I have tried a pram reset and smc reset, and replaced the pram battery as well. When booting , the computer will load the grey apple screen like normal and then go to a blue screen that it hangs on for about 3-5 minutes. After getting logged in the computer runs fine. If the computer is put in sleep mode, its non responsive and has to be hard reset to get it running again.