On Jun 8, 19:18, Jerome H. Fine wrote: Jay, could you look at the ROMs on your RXDXen and see what the 23-xxx numbers are? just The difference between RQDX1 (M8639) and RQDX1 (M8639-YA) is just the ROMs, which were field-upgraded, so check the ROM numbers not the handle. Only the third version is -YA, which supports RD52. The first version has problems with RX50s. V.7.0 23-238E4 and 23-239E4 V.8.0 23-264E4 and 23-265E4 V.9.0 23-042E5 and 23-043E5 M8639-YB is not RQDX3, it's RQDX2. There were three versions of the ROMs for this, and only the last two supported RD53. The difference between M8639[-YA] and M8639-YB is a diode and some hackery in the top left corner; this too could be done in the field so don't rely on the handle number. The purpose was to eliminate the "must be last card in backplane" problem. V.9.4 23-172E5 and 23-173E5 V.10D 23-178E5 and 23-179E5 V.10E 23-188E5 and 23-189E5 The RQDX3 also had several versions of its "microcode", and the first doesn't directly support RD3x (it has other problems too). The first three or four have problems with anything bigger than an RD53. ??? 23-166E5 and 23-167E5 V.1.10 23-216E5 and 23-217E5 V.2.? 23-243E5 and 23-244E5 V.3.? 23-285E5 and 23-286E5 V.4 23-339E5 and 23-340E5 (RQDX3-F002 / EQ-01532-02) I'm not sure if the 23-166E5 and 23-167E5 really exist; I have every version of the RQDX3 ROMs except those, and the numbers may be a typographic error (as implied in one of the FCOs). Or else they were so bad they were replaced before or very quickly after the RQDX3 release. I also have the RQDX1/2 ROMs versions 7, 8, 9.0, 9.4, 10E, but not 10D. -- Pete Peter Turnbull Network Manager University of York