HP Kayak XU800 Series, Technical Reference Manual

Page: 66 / 140

66
2 System Board
Host Bus
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
and Windows 2000 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
SMP-
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 have the same speed.
Configuring for
Multi-Processing
HP Kayak XU800 PC Workstations support Symmetric Multi-Processing
(SMP). When a second processor is added, it is automatically detected so
there is no specific configuration required.
The “mono-processing” mode has been implemented in order to support
operating systems that rely on the “legacy” interrupt controller 82C59 and
are not aware of I/O APIC controller operation. Refer to
page 68 for further
details.
Processor Clock
The 100/133 MHz Host Bus clock is provided by a PLL. The processor core
clock is derived from the Host Bus by applying a “fix ratio”.
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.