Did Microsoft update KB4494441 re-write the microcode in my BIOS?

[bbhaag]

I was am curious about Microsoft's latest update labeled KB4494441. According to the improvements and fixes section it mitigated something called Retpoline and a Spectre Variant 2. Can anyone help me understand what this update did? Is it a good thing? I'm kinda tech savvy but when I searched what I read went way over my head. Can anyone dumb this down for me so I can understand it or have a link that explains this for computer novices like me.

 

[JackMDS]

This is the way it works in the last few years.

Microsoft is making available Intel-validated microcode updates.

https://support.microsoft.com/en-us/help/4093836/summary-of-intel-microcode-updates

 

[SPBHM]

it loads the newer microcode during boot, it doesn't touch your bios

 

[bbhaag]

Thanks for the info guys I appreciate it. I just wasn't sure so I thought I would ask.