I was running Ubuntu 12.04 LTS and was accepting all suggested upgrades. About a week ago I was prompted to upgrade the Hardware Enablement Stack because it was going out of support. So I did and I upgraded to 12.04.5. Unfortunately this upgrade brought multiple problems to my computer: if I send computer to sleep it does not recover, and if I shut it down, it restarts automatically for now apparent reason.
Now I want to undo the upgrade that I made last week. Is there a simple way to do that?
glmark2
benchmark (see my question here).