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2 System Board
Host Bus
In a dual-processor system, the CPU core to FSB frequency ratio is always
the same for the two processors ensuring that the two processors will always
run at the same speed.
Bus Frequencies
There is a 14.318 MHz crystal oscillator on the system board. This frequency
is multiplied to 133 MHz by a phase-locked loop. This is further scaled by an
internal clock multiplier within the processor. The bus frequency and the
processor voltage are set automatically.
Voltage Regulation
Module (VRM)
Two VRMs are integrated on the system board complying with VRM
specification, rev. 8.2 and 8.4. High-current and low voltage processors are
supported.
Processors require a dedicated power voltage to supply the CPU core and L2
cache. Each processor codes through Voltage Identification (VID) pins with
a required voltage level of 1.5 V to 3.5 V. Each VID set is decoded by the
VRM on the system board that in return supplies the required power voltage
to the processor. It should be noted, however, that voltage may vary from
one processor model to another.
Optional Second Processor
Single processor models can be upgraded to a dual processor system by
installing a second processor in the vacant slot. The second processor must
be a Pentium III processor for Slot 1 of the same speed and Level 2 cache
memory capacity as the first, and same Level 2 cache voltage.
NOTE
When upgrading a processor or installing a second processor, the processor
type and speed is automatically recognized by the BIOS. This means that no
particular switch settings are required.
Upgrading a single processor to a dual processor system on Windows NT
platforms is made easier with the HP DualExpress! application which is
included in the HP processor application kit.
Installing a second processor is only advantageous when the software can
make use of parallel activity. In particular, you need to be running a multi-
threaded operating system that supports multiprocessing (one that is
MPS-
ready
), such as Windows NT. The Windows NT operating system makes the
best use of the Pentium III 32-bit architecture (though other operating
systems will also show some benefit if 32-bit application programs are run).
The two processors must be operating at the same speed.
