VAX 11/750 power requirements

--- Matthew Sell <msell(a)ontimesupport.com> wrote: That sounds just about right. If you have the last rev of the memory controller, you can drop a couple of 4MB boards in there, but they were never common. I personally upgraded my original 11/750 from 2MB to 8MB when it was still owned by my employer. The upgrade was to add a backplane wire for the extra address line, stick the new mem controller in, and change a switch on the backplane switch register. I do not know what's involved with upgrading an 8MB 11/750. It is probably similar. Never had an FPU for ours, but it does have a Massbus controller (for our TU78), an Systems Industries SI9900 controller (in another Massbus slot), and at one point, we had an L0010 "2nd Unibus" card (don't recall if it's in there at the moment). It _might_ have another Massbus adapter in that slot since at one point, we did have a pair of RM03s as stand-by system disks in case our SI9900 or its 160MB Fuji SMD drive failed. Nice system. Ours was the office machine for 60+ people, including software developers, sales, office admins, etc. 8MB of RAM, and as long as we rode herd on the users to get out of their apps when they were idle (VMS MAIL and MASS-11, our word-processing app, had about 1MB of resident storage plus whatever was needed for working space for each user), we paged, but we almost never swapped. One way to reduce the draw of the 11/750 itself would be to not use the internal Unibus. Grant all the slots and use an external BA-11. You might draw more overall current that way, but you could put them on seperate branches. For as many users as we had, plus as many disk and tape devices as we needed, we *filled* the internal Unibus, and had a BA-11 at about 50% capacity, but we had RX50, RL02, SDI disks (RA81s typically), 64 terminal lines, line printer, several COMBOARDs for SNA and Bisync, etc. Nice machines if you can stand .6 VUPs and live within the memory it provides. For a Unibus-oriented machine, it's probably my favorite. A low-end VAXBI machine *with* a Unibus is almost a substitute, but not quite. -ethan __________________________________________________ Do you Yahoo!? Yahoo! News - Today's headlines http://news.yahoo.com