For some reason my i5 8400 only boosts to 3.5 ghz after I swapped my motherboard from an hp to a gigabyte b365 ds3h. On the hp motherboard it would hold 3.7-3.8 ghz under full load at 75 degrees celcius. On the new motherboard it will only hold 3.5ghz under full load and under 50 degrees(cuz new cooler). I went on to change some bios settings and stuff with no success. If anyone knows how to fix this then please help.