[ubuntu] iMac won't boot after upgrade / kernal install

view story

http://ubuntuforums.org – Strange problem. Ubuntu works fine on my iMac if I choose previous kernals and use kernal 2.6.....25. (Don't know exact string). The newest kernal that was installed after my upgrade was 2.6.....32. I try booting into that kernal and it just goes to black screen after about 20 seconds. About 50% of the time I get a boot loader, and then black. Other times I get black instantly after grub. Any thoughts? I have a Intel Core i3 3.07 GHZ Imac 27 inch. 32 bit Ubuntu. (Hardware)