Boot into your bios and check your temperature readings in there as well.
Your max temp for your CPU is 85c so you don't want to be getting higher than about 75c to be safe. If your IDLE temps are 54, you may be OK (sounds a little high) but what we need to know are your temps at full load. Do you have any games loaded into your computer? If you can, run a game for a few minutes, then check your temps again to see how hot it is getting.
Other than that, go through the steps in my signature for random crashes and see if you can't rule out some things as possible causes.