What you have to remember is that we are having hotter weather than the Med. at the moment so all CPU temps will rise a little.
54C is ok, just forget about it. The intel chips have clever workings. So if the CPU should go above a preset temp it will turn itself off. So it will save it self...
Also if your case is up against a wall or you have lots of stuff around it. Move the case out and give it some air flow.
Also dust can make temp go up so umm DUST the inside of the PC.
But i would just ignore the temp and get computin'.