I have a Lenovo G460 running 10.7.4 very smoothly without any problems. i have a pre edited DSDT. I successfully installed mountain lion gm and it booted up fine but after a few minutes from boot it always hangs. System completely freezes and i can't even move the mouse. The laptop also heats up.
Additional kext that i use apart from vanilla are :
PS2 keyboard and mouse kexts
I do not use NullCPUPowerManagement.
Any solutions for this??