HP Digital AlphaStation 255 Family User Information page 118

Technical Specifications
Table B–13: Motherboard Switch Settings (continued)
Timer/Counter (TC)
Audio Disable
5
Off
On
CPU Speed Switches
6 7
On On
Off On
On Off
Off Off
On On
Off On
On Off
Off Off
B–12
Function
Enables TC sound
(Default)
Disables TC sound
CPU Clock Rate
8 (MHz)
On 133
On 166
On 200
233
On
Off 266
Off 300
Off 333
Off 366
Description
Switch 5 controls the use of timer/counter
(TC) generated sound. The default position
(Off) is used when no sound driver is
installed. There is no volume control for
TC sound.
Description
These switches set the CPU clock speed. In
order to run your system at a higher speed,
you must install the appropriate CPU
upgrade kit.