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CHAPTER 3: HARDWARE INSTALLATION
THE DRAM SIMMs
The on-board DRAM memory subsystem has three module mounting
sockets which are divided into "banks' of one socket each. They support
512Kx36, 1Mx36, 2Mx36, 4Mx36, and 8Mx36 DRAM SIMMs. These
banks are labeled SIMM1, SIMM2, and SIMM3. DRAM speed must be
80ns, 70ns, or 60ns. You can configure the memory of the 486MIS in a
variety of ways. The chart below shows the possible combinations.
Total
Memory
SIMM1
SIMM2
SIMM3
2MB
512Kx36
None
None
4MB
512Kx36
None
512Kx36
6MB
512Kx36
None
1Mx36
4MB
1Mx36
None
None
8MB
1Mx36
1Mx36
None
12MB
1Mx36
1Mx36
1Mx36
20MB
1Mx36
4Mx36
None
24MB
1Mx36
1Mx36
4Mx36
40MB
1Mx36
1Mx36
8Mx36
8MB
2Mx36
None
None
12MB
2Mx36
None
1Mx36
16MB
2Mx36
None
2Mx36
24MB
2Mx36
None
4Mx36
40MB
2Mx36
None
8Mx36
16MB
4Mx36
None
None
32MB
4Mx36
4Mx36
None
48MB
4Mx36
4Mx36
4Mx36
64MB
4Mx36
4Mx36
8Mx36
32MB
8Mx36
None
None
48MB
8Mx36
None
4Mx36
64MB
8Mx36
None
8Mx36
486MIS System Board User's Manual Page 21