I've been experiencing the same freezes as the OP. As far as I understand, there are 2 types of freezes described in these forums:
- freeze type 1: desktop freezes, but the mouse still moves, and it is still possible to go to the login screen using ctrl+alt+backspace
- freeze type 2: complete freeze, where it is not possible to go to the login screen using ctrl+alt+backspace, nothing responds (includig the mouse), only option left: pressing the power button on the computer
Freeze type 1 seems to be a cinnamon issue. Clem has provided alternate builds of cinnamon for us to test: see viewtopic.php?f=90&t=103054&start=440
. These build do NOT fix the crashes I'm experiencing (freeze type 2).
Freeze type 2: it seems the OP experiences this type of freezes, like me. His CPU is an Intel i5 Ivy Bridge (identical to mine). There might be a problem with the Intel driver in the current kernel. See bug report: https://bugs.launchpad.net/ubuntu/+sour ... bug/993187
Comments #85, #86 and #91 in the bug report are interesting. Comment #91 provides guidelines for installing the kernel 3.3.6 in Ubuntu 12.04. I tested this procedure in Mint 13 and it works. I'm not sure yet if this solves the hard freezes, because I've only been testing for about 1 hour since installing and running kernel 3.3.6. However there seem to be some positive reports in the bug report.