System Software Constraints For Sxdram Configuration; Recommended Dsimm/Vsimm Configuration For The Sparcstation 10Sx - Sun Microsystems SPARCstation 10SX System Configuration Manual

System Software Constraints for SXDRAM
Configuration
The following constraints are described in terms of the SPARCstation 10SX, but the
same concerns apply to the SPARCstation 20.
1. The first slot (slot 0) must always be configured with a DSIMM.
2. The minimum recommended amount of memory required for reasonable
SPARCstation 10SX performance is 32 MByte. Thus, to be able to reserve
SXDRAM, a system should be configured with more than 32 MBytes of DRAM.
However, users can configure the minimum amount of memory that must be
reserved for system use by using the -l option of the sxconfig (1M) command. The
difference between the amount of DRAM installed on the system and the
configured minimum limit (32 MBytes by default) is the maximum amount of
memory that can be reserved for SXDRAM.
3. The amount of physically contiguous memory that should be reserved must be
specified as an integer multiple of 1 MByte. Thus, the minimum amount that can
be reserved is 1 MByte.
Recommended DSIMM/VSIMM Configuration
for the SPARCstation 10SX
1. The VSIMM can only be installed in slots 4 or 5 on the SPARCstation 10SX. If
there is only one VSIMM, it can be installed in either slot 4 or 5. To install the
VSIMM in slot 5, an AVB (Auxiliary Video Board) card is required. This card is
not bundled with the SPARCstation 10SX.
2. Always install a 16 MByte DSIMM in slot 0 when you have a combination of 16
MByte and 64 MByte DSIMMs.
3. If the memory system consists only of 16 MByte DSIMMs. They can be configured
in any slots, provided that the first 16 MByte DSIMM is installed in slot 0.
4. Within a memory bank, always install the DSIMMs in the order of decreasing
DSIMM sizes (the ordering does not matter if all the DSIMMs are of the same
size). In other words, if there is a combination of 64 MByte DSIMMs and 16
MByte DSIMMs, install the 64 MByte DSIMM in the lowest-number slot, followed
by the 16 MByte in the immediate next slot.
When configuring the memory subsystem with 64 MByte DSIMMs and 16 MByte
DSIMMs, the following examples can be used as a guide:
System configuration: 1 VSIMM, 2 16 MByte DSIMMs, 2 64 MByte DSIMMs.
Chapter 2 Reserving DRAM for SX Accelerated Applications 9