XTIDE is OK. It's nicer than disk overlays most of the time. Might be the best you are going to do on something that's a 286 or older.
However look around to see if you can find an MR Bios for your mobo. That's the way to go. It's the premium ride.
I have an FIC PT-2003. The old bios was fussy, 528MB limited, and unclear.
I found the MR Bios for it. Feels feels like a painful splinter was removed from my foot.
It's like the person who wrote it actually cared if I was happy or not.
Features like large drives, readable menus, and a configurable hot key to go straight to the bios while in DOS without testing my keyboard reflexes.
Or hot keys to go straight to the boot menu. Or enable/disable disable L2 cache on the fly. Crazy fun stuff.
How about a MR-BIOS ROM file repository?