I have several FSBE/S (X1053A, sun part # 501-2015) cards in my NetBSD systems, all of which are SPARC Classic or SPARC LX (sun4m). NetBSD 1.2 and 1.2.1 does not support them. NetBSD-current (and 1.3) do. Works great. I'm sure the card will work fine in your IPX. I have one in an SS2 running SunOS 4.1.4... Erik <fair@clock.org>