new board old hard drive

[cptmac]

I want to upgrade my mother board and the processor. This the first time I’ve tried this. Once the new board is installed, connect the old hard drive (with the existing OS), will the system drive on like nothing happened or will the new BIOS pop up and start asking questions? Thanks.

 

[BUFF]

Windows will probably fall over at the driver loading stage.
You can do a repair install.