What's the difference between an OROM driver ("option-ROM") and a "regular" Windows-level driver?
I see a lot of chatter amidst the BIOS-modding community about OROM drivers (modules?) and Windows-mode drivers, specifically relating to Intel RAID driver updates. It seems that it's important to update both the OROM driver and the Windows driver. I've never known about two sets of simultaneous drivers for a device.
What's the difference between them, and why are two drivers necessary? What would happen if one is significantly older than the other? (Purely hypothetical for understanding -- I'm not troubleshooting)