Processor And Secondary Cache; System Bios - NEC POWERMATE PROFESSIONAL - SERVICE MANUAL 05-1997 Service Manual

Processor and Secondary Cache

The PowerMate Professional uses a Pentium II processor with an internal clock speed of
233 MHz or 266 MHz. The external speed of the 233-MHz and 266-MHz processors is
66 MHz.
Each processor has 32 KB of write-back primary cache and a math coprocessor. The
32-KB primary cache provides 16 KB for instructions and 16 KB for data.
The processor is an advanced pipelined 32-bit addressing, 64-bit data processor designed to
optimize multitasking operating systems. The 64-bit registers and data paths support 64-bit
addresses and data types.
To use the Pentium II processor's power, the system features an optimized 64-bit memory
interface and 512 KB of secondary write-back cache incorporated into the processor.
The processor is compatible with 8-, 16-, and 32-bit software written for the Intel386™,
Intel486™, Pentium, and Pentium Pro processors. The Pentium II processor is contained on
a Single Edge Contact (S.E.C.) cartridge that plugs into the system board at Slot 1, which is
a 242-pin edge connector. The processor subsystem consists of the following components:
T
processor card (including the processor and secondary cache)
T
thermal plate
T
back cover.
When the processor subsystem is mounted in Slot 1, it is secured by a retention mechanism
(RM) attached to the system board. The RM acts as an insertion guide and prevents
movement of the processor after installation. The processor heatsink is also stabilized by
supports that attach to the motherboard.

System BIOS

The system BIOS is from Intel/American Megatrends Incorporated (AMI) and provides
ISA and PCI compatibility. The BIOS is contained in a 2-MB flash memory device on the
system board. The BIOS provides the Power-On Self Test (POST), the system Setup
program, a PCI and IDE auto-configuration utility, and BIOS recovery code.
The system BIOS is always shadowed. Shadowing allows any BIOS routine to be executed
from fast 32-bit onboard DRAM instead of from the slower 8-bit flash device.
NEC's Flash ROM allows fast, economical BIOS upgrades. NEC Flash ROMs are
reprogrammable system and video EPROMs. With NEC's Flash ROM, a ROM BIOS
change is expedited in the following ways:
T
is fast and easily done using a Flash utility
T
eliminates the expensive replacement of ROM BIOS chips, and reduces system
maintenance costs
Technical Information 1-7