I5-7600k not reaching speeds I set in bios

[masterchicken]

My pc has a 7600k and this motherboard i recently started testing some mild overclocks, for the past month i have been running 4GHz no problem, up from the stock 3.8. But my bios for some reason isn't allowing me to enter a multiplier higher then 42. and even weirder, no matter what stress test/load i put on it, with the multiplier at 42 in my bios, task manager and HWmonitor both show my cpu's clock speed at 4GHz  even though it should be at 4.2 from what i understand.

I'm new to overclocking and any help would be appreciated 

[Ashiella]

The b250 series boards arent supposed to be able to overclock if I recall correctly. You need a z270 board.

[unclewebb]

http://www.cpu-world.com/CPUs/Core_i5/Intel-Core i5 i5-7600K.html

 

When not overclocking, the max multiplier for the 7600K when 4 cores are active is 40.  The max when 1 core is active is 42.  Without a Z series board, those are going to be your limits.  Make sure the Core C States are enabled in the bios to take advantage of Intel Turbo Boost.

[masterchicken]

4 minutes ago, unclewebb said:

http://www.cpu-world.com/CPUs/Core_i5/Intel-Core i5 i5-7600K.html

 

When not overclocking, the max multiplier for the 7600K when 4 cores are active is 40.  The max when 1 core is active is 42.  Without a Z series board, those are going to be your limits.  Make sure the Core C States are enabled in the bios to take advantage of Intel Turbo Boost.

 

7 minutes ago, Ashiella said:

The b250 series boards arent supposed to be able to overclock if I recall correctly. You need a z270 board.

well, that would explain it. thanks for the help