TYAN S1668 Dual Pentium Pro ATX 440FX PCI-ISA System Board User's Manual

13S1668-ATX-001 http://www.tyan.com
3.10 DRAM Installation
The S1668 uses a 64-bit data path from memory to CPU and can
accommodate up to 1024 MB of RAM. The mainboard supports
standard, EDO (Extended Data Out) and ECC(Error Correcting Code)
72 pin SIMMS . All installed memory will be automatically detected so
there is no need to set jumpers.
 SIMM modules must be installed in pairs.
 Each pair of SIMMs must be of the same size and type.
 The mainboard supports 1, 2, 4, 8, 16x32 or 32MBx32 SIMMS.
 The table on the following page shows some of the available memory
configurations.
Voltage ID for Older Pentium Pro CPU's: J10 and J20
Most Pentium Pro CPU's will program the VRM to output
the correct voltage it requires, so these jumper are not important
and should be left open. Some early versions of the Pentium Pro
cannot program the VRM so you have to set these jumper manually.
J10 and J20 each have eight pins and are numbered as follows.
5 6 7 8
1 2 3 4
Pin # 4--8 3-7 2-6 1-5
3.5V o n o n o n o n
3.4V o n o n o n off
3.3V o n o n off on
3.2V o n o n off off
3.1V o n off on o n
3.0V o n off on off
2.9V o n off off o n
2.8V o n off off off
2.7V off o n o n o n
2.6V off o n o n off
2.5V off o n off o n
2.4V off o n off off
2.3V off off o n o n
2.2V off off o n off
2.1V off off off on
Default off off off off