[comp.sys.next] 4 MB SIMMS prices? Anyone put 4 MB SIMMS in their cub

smithw@physc1.byu.edu (03/20/90)

   If you look in /NextLibrary/Documentation/NeXT/SysRefMan Chapter 17
page 7 (ROM monitor stuff) you see the following:

   NeXT> m

   Memory sockets 0-3 have 4MB SIMMs installed

         (0x4000000-0x4400000)

   Memory sockets 4-7 have 16MB SIMMs installed

         (0x5000000-0x6000000)

   Memory sockets 8-11 have 4MB page mode SIMMs installed

         (0x6000000-0x63fe000)

   Memory sockets 12-15 have no SIMMs installed  (0x0-0x0)

This looks like it *may* be actual ROM monitor output from
some lucky so and so.  16MB SIMMs???  Anyway, looks like you
have to install SIMMs in 4 slot blocks but with that restriction
they can be any size? NeXT -- care to comment?

anders@penguin (Anders Wallgren) (03/20/90)

Well, on my cube, with 8MB it says something like:

   Memory sockets 0-3 have 4MB SIMMs installed
         (0x4000000-0x4400000)
   Memory sockets 4-7 have 4MB SIMMs installed
         (0x5000000-0x6000000)

and I certainly don't have any 4MB SIMMs installed, which leads me to
believe that that number refers to the total memory present, as
opposed to the size of each SIMM.

anders

fischer@iesd.auc.dk (Lars P. Fischer) (03/21/90)

In article <56smithw@physc1.byu.edu> smithw@physc1.byu.edu writes:
>Anyway, looks like you
>have to install SIMMs in 4 slot blocks  ...

Well, the bus is 32 bits wide and a SIMM is 8 bits wide. As you can't
leave one "side" of the bus empty, you must add SIMMs in blocks that
fill the width of the bus.

/Lars
--
Lars Fischer,  fischer@iesd.auc.dk   | Q: How does a project get to be one
CS Dept., Univ. of Aalborg, DENMARK. | year late?  A: One day at a time.