amd fx-6350 oc to 4.2ghz / core 5 not stable

[bidmoon]

hi, i was messing around with my CPU and overclocking it, and everything seems to work fine. I was running prime95 and saw that my core 5 wasn't running at 100%. it was bouncing around 5-8% and im wondering what could have caused this? The temperatures seem fine below 40c, its just that 5th core of the cpu.

http://i.imgur.com/rCxgCut.png

my rig-
990fxa-ud3
AMD fx-6350
ram - 2x4 corsair 1600mhz
hyper 212 evo
psu -thermaltake toughpower 750w

 

[envy14tpe]

You are choosing a value at one instant. I mean, the values will fluctuate based on needs. If you really want to look at one variable like CPU usage then download Open Hardware Monitor.
go to the top of Open Hardware Monitor - Click View > Show Plot
This way you can track the cpu usage with time.