All Baby Voyager Boards with ECN 001/ECN 002 could have problems with I/O cards that are accessing memory locations in the E0000h - EFFFFh address segment. This is because in ECN 001 and ECN 002 level boards, this area is cached in the 80486 internal cache. This problem might appear with a number of serial intelligent I/O controllers for UNIX as well as certain communication cards, etc.
The modification generated by ECN003 does not allow the contents in the E0000h - EFFFFh address segment to be cached in the internal cache of 80486.