Battlefield 1 not using full core clock speed?

[kol12]

I have a perfmon graph here while playing Battlefield 1 and to my surprise it's playing with a core clock speed of only 3.5Ghz whereas I'm overclocked to 4.2Ghz. Any idea what's happening here?

 

[kol12]

Well if I add core clock to the OSD of MSI Afterburner from HWiNFO it shows the clock speed as being 4.3Ghz while playing the game. So why is performance monitor not reading the correct frequency? I want to track what the frequency is doing while SpeedStep is on.