Specifications

1.3.1.1 Option Module Slots

Eight extended industry standard architecture (EISA) option slots are available

on the system board. The slots are industry standard architecture (ISA)

compatible, so both EISA and ISA option modules can be installed.

Six of the EISA slots are EISA master slots. EISA master modules must

be installed in EISA master slots. EISA master modules are devices which

assume control of the bus for activities such as direct memory access (DMA).

ISA modules and EISA slave modules may be installed in any slot.

Note

When you replace the system board, always install the modules in the

same slots from which they were removed.

1.3.1.2 System Board Jumpers

System board jumpers allow you to set certain system options. For more

information, refer to Appendix B.

1.3.1.3 Real-Time Clock Chip

The real-time clock chip, which contains a lithium battery, provides power for

nonvolatile memory when power is removed from the system.

1.3.2 CPU Module

The CPU and all associated speed-dependent components are isolated on a

separate CPU module. Upgrading a system is as easy as removing the current

CPU module and replacing it with a faster CPU module. The system can be

conﬁgured for use with the following Intel 80486 CPU modules.

• 25 MHz Intel 486SX

• 33 MHz Intel 486DX

• 50 MHz Intel 486DX

The 25 MHz and 33 MHz CPU modules contain a socket for installation of an

optional 64 or 128 KB cache card. The 50 MHz CPU module comes standard

with 256 KB cache installed.

System Overview 1–9