Discussion i7 4790 (non k) only at 3.8 ghz

Jan 28, 2020
im currently running my i7 4790 at 3.8ghz fixed mode with turbo boost off and when i try setting the it to 4.0ghz it caps down to 3.8ghz i havent messed with any setting in bios because i dont really know what they mean.but i just need help getting as much performance out of my cpu as possible any reply's help alot :)

My Specs
i7 4790 Core speed(3800.11mhz) Multiplier (x38.0) Bus speed (100mhz)
16gb ddr3 1600mhz
gtx 1070
msi z97 gaming 5 v1.12