Hi again, Guys I still have a problem to get my qbus VAx Memory boards working thogether. I do have an KA630CPU, Firmware 1.30, and want to get 2 8MB Memory Boards to work thogether in a H9278 Backplane which has 3 CD interconnect slots. I've tried all variants ot plug the boards and of the switch and Jumper settings. The one board is an National NS638 the other is a Chrislin CM-VI-8. For the memory sizing test I'm booting NetBSD 1.5.3 over the network from my FreeBSD Workstation. There are setting where I get a double fault while booting, think that is why there is to small amaount ov memory enabled. Mostly I get 9MB of Memory (1MB from the KA630 + one 8MB Board) but I had 10Mbytes too so that at least one of the boards must have worked as 1MB Mem. There is also a setting where the machine doesnt boot at all. The NS638 has a Jumper that can be set into the W1 and W2 positions, have tried both of them. I have additionally an MS630 Board with 4MB of memory, this board works thogether with the crislin and the national board, I get 13MB of memory total (8+4 +1MB KA630). An other MS630 with only 2 Mbytes is still untested. So please, please, does anyone here know whats happening here and what for the jumpers and the switches on the handles of the 8MB boards are for? Has anyone those boards too and can confirm this? Regards, Holm -- Technik Service u. Handel Tiffe, www.tsht.de, Holm Tiffe, Freiberger Stra?e 42, 09600 Obersch?na, USt-Id: DE253710583 www.tsht.de, info at tsht.de, Fax +49 3731 74200, Mobil: 0172 8790 741