There are several sites citing the problems related with the Sandy Bridge of Intel which is fairly new.
You have 2 types of problems: Hardware problems and Kernel problems.
Kernel Problems
In the Linux kernel, does not matter what version of Ubuntu or what other distro you use, you will still see the problems with the kernel and power regressions. Of course the latest version have more problems but older versions will still several power related issues.
Hardware Problems
Without mentioning EVERY LINK that mentions problems about hardware for the Sandy Bridge you could do a google search just for Sandy Bridge and you will see several of them. some of which are:
http://www.phoronix.com - Which mentions power regressions, video problems and cpu problems.
http://hardware.slashdot.org/ - which mentions really big heat problems
http://www.pcmag.com/article2/0,2817,2379241,00.asp#fbid=xZbYR5U-2nn - Mentions some of the hardware problems related to Sandy Bridge. Some of which have been solved.
Basically you discovered one of several problems related to a chipset/cpu/kernel problem.
Sounds horrible I know (Me being an Intel follower) but am hoping that Ivy Bridge will solve this with not only eliminating all video/chipset/cpu problems but adding new technology that guarantees that we will not see this horrible problem.
sudo lshw
in a terminal and paste the output into your question.