Question Could downgrading bios solve CPU problem?

Dec 21, 2018
Hi guys, so im having troubble with my H81M-C motherboard + my new Intel Core i7-4790K CPU.

Before this CPUi was using a Intel Core i5-4670 CPU.

When booting with the newer CPU the fans start and the computer does not turn itself off, but the screen remains black so i have no idea if it boots to bios, windows or not at all.

Swapping back to the older CPU and i get screen and everything works, it says "New CPU installed! in bios"

Ive tried unplugging Rams, made sure the CPU works in another computer etc.

Im using a bios version called 3602 which is the latest for the motherboard - was released 26 mars 2018.

Ive got the tip of downgrading the BIOS of my motherboard from both a friend and on here, but i dont see anything about someone solving a problem that way online.
What do you guys think? Is it worth attempting? or is it just a waste of time?