mykebrian :
I have a core i3 2120. Has anyone tried using their cpu without a thermal compound?
Yes,I am using it without thermal paste from approximately 2 years.
Problems which occurred while
In summers:-
The only possible effect of not using it is that it may not result in heat dissipation properly and letting your system heat up fast unusually.
Sometimes system gets automatic restarts to protect the processor from overheating on load.
In Winters:-
The effect of auto-restarting of system is minimum.
The thermal compound will give you a few degrees difference but it is really worth it.
Are you experiencing any problems?
It is better to use the thermal compound rather then avoiding it.