Screen freezing randomly.

Tried verify and repair disk, or permission. Reinstalled mountain lion and using migrate from my time machine backup. Nothing happen, still screen freeze randomly and the mac just crashes.

Spec of my mac:

-early 2011 macbook pro 15"

-2.2 Ghz I7

-AMD 6750 1gb

-OS X 10.8.3 (12D78)

After every time forced shut down (holding power), found these line from console repeating massively times:

4/3/13 7:58:45.000 PM kernel[0]: Trying restart GPU ...

4/3/13 7:58:45.000 PM kernel[0]: AMDTurksGraphicsAccelerator: bad busy count (255,1)

4/3/13 7:58:45.000 PM kernel[0]: Backtrace 0xffffff8008e2c048 0xffffff8008e2bf54 0xffffff7f8a5d74e7 0xffffff7f8a5cb0ac 0xffffff7f8a5cbe15 0xffffff7f8a5d0c42 0xffffff7f8a5e9411

4/3/13 7:58:45.000 PM kernel[0]: Kernel Extensions in backtrace:

4/3/13 7:58:45.000 PM kernel[0]: com.apple.iokit.IOAcceleratorFamily(30.14)[8CAD17E4-8359-3015-BCFC-F1964357CBFE ]@0xffffff7f8a5c5000->0xffffff7f8a60ffff

4/3/13 7:58:45.000 PM kernel[0]: dependency: com.apple.iokit.IOPCIFamily(2.7.3)[1D668879-BEF8-3C58-ABFE-FAC6B3E9A292]@0xffff ff7f89044000

4/3/13 7:58:45.000 PM kernel[0]: dependency: com.apple.iokit.IONDRVSupport(2.3.7)[38C214C0-83C8-3594-8A4C-DC6AC3FEC163]@0xff ffff7f89e92000

4/3/13 7:58:45.000 PM kernel[0]: dependency: com.apple.iokit.IOGraphicsFamily(2.3.7)[74E3E50F-E50A-3073-8C96-06F854292A91]@0 xffffff7f89ddf000

4/3/13 7:58:45.000 PM kernel[0]: GPU Hang State = 0x00000000

4/3/13 7:58:45.000 PM kernel[0]: GPU hang: Not Implemented

4/3/13 7:58:45.000 PM kernel[0]: Trying restart GPU ...

Hope someone can tell me what happen, have no trouble using and playing games on the bootcamp which is operated by Win 7 64bit.