M4600 Any working Fancontrol Software? Can I update M4600 Bios (A19) with Bios from a higher Laptopmodel?

Hello!

Got an veryyyy old M4600, but still with good Hardware for surfin andwatching YT...

Nvidia 2000M, core I5-2520, 8GB RAM, 256 SSD ...

Problem is the I5-2520. Clock up, down, up...temps idle up down between 50-70, Dell Powermanager, all Profiles tested, Energy Options all tested, even disabled the Boost. Disassembled and new Arctic paste on the cpu/Gpu, all cleaned inside, Fans and and ...

But the Fan still starts up from about 55° every 1,5 Minutes or less, when just surfing Ebay or watching YT. And it ALWAYS starts with 2500RPM from 3700 he is able to. Never less, always minimum 2500RPM and thats a bit too loud.

Tested at least 5-8 Fancontrol Softwares, not even one could steer the fans of the M4600.

Any Idea how to solve this?

Or is it possible/did someone tried to update with a BIOS from a 4700/4800/6600? Some of them should have Fanfunctions in their Bios, mine has none... :(

Thanks in Advance!

Regards

Jack