Comment 43 for bug 451518

This may be related to DVMT; Intel's Dynamic Video Memory Technology. ... its supposed to work with Microsoft's proprietary driver to dynamically allocate video memory resources (up to 128 M) for 2D - 3D performance and then return the memory resource to the OS when finished. My machine defaults to 8M preallocated, 0M fixed, and 120M DVMT...

I changed the default settings to 8M preallocated 120M fixed and 0M DVMT... and the freeze is gone... even with compiz.real running w/ screensaver. I left the silly thing running all night... no problems.

Perhaps the i915 driver isn't working well with DVMT ; Intel integrated graphics chipset 915 945 ?

regards,
m harris