Sun Microsystems SunSwift SPARCserver 1000, Manual

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A-2 SPARCserver 1000 System Board Manual—October 1994
A
•
When additional memory is added to a system, the new SIMMs should be
always be installed in the lowest available group, regardless of the board on
which the SIMMs are installed.
•
When adding memory to a system, begin with the system board in the
lowest available card cage slot number and fill the lowest open group. Then
fill the lowest available group on the system board in slot 1, etc.
•
To optimize memory performance, keep the numbers of memory groups
balanced across boards, in multiples of two or four boards (This allows the
system to interleave memory across boards.) For example, if there are three
boards in the system, and a total of four SIMM groups, fill both group 0 and
group 1 on the first two boards. Memory added to the third board is usable,
but it cannot be interleaved with memory on the first two boards (unless a
fourth board with memory in a matching group location is also added.) If
this memory is accessed often, performance will suffer.
Figure A-1 SIMM Group Locations on the System Board
The SIMMs on a system board are divided into four groups, as summarized in
Table A-1.
J2800
J3200
J3600
J4000
J2900
J3300
J3700
J4100
J3000
J3400
J3800
J4200
J3100
J3500
J3900
J4300
Group 3
Group 2
Group 1
Group 0
Group 3
Group 2
Group 1
Group 0
Group 3
Group 2
Group 1
Group 0
Group 3
Group 2
Group 1
Group 0