Hi Max,
According to the pictures, R2.0 differs from R3.0 by the number of PCIe slots (maybe some ports will not work) and it looks like they are using a different SuperIO chip (you may not see the console in the COM port), maybe there are other differences... Regardless, you can try to run coreboot on your board, although I recommend analyzing the pad configuration using inteltool (get a dump of the registers of the gpio controller):
$ sudo ./inteltool -G
and then compare this with the dump from R2.0 - https://github.com/maxpoliak/inteltool-examples/blob/master/inteltool-asrock... https://github.com/maxpoliak/inteltool-examples/blob/master/inteltool-asrock-h110m-dvs.log
If there are differences, then you need to fix them in https://github.com/coreboot/coreboot/blob/master/src/mainboard/asrock/h110m/... https://github.com/coreboot/coreboot/blob/master/src/mainboard/asrock/h110m/include/gpio.h
This will avoid possible burnout of chips, transistors or any other elements on the board.
Thanks for the information. I don't have a board with me since I was just considering buying one that's compatible with coreboot. It looks like none of the other boards are suitable for my purposes unfortunately.
Best regards, Alex