Cache; System Speed; Memory At 15Mb-16Mb; Fixed Disk Power Saving Mode - Mitsubishi XEN-PC apricot Owner's Handbook Manual

Using the SETUP utility
By copying the BIOS into RAM the system takes advantage of
the shorter access times of RAM. An additional benefit is that
shadowed ROM spaces are cached gaining a further performance
advantage.
ISA bus (C8000h - EFFFFh)
BIOS on any expansion cards is stored in ROM which has long
access times. Enabling BIOS shadowing enhances performance
by copying the contents of the ROM into RAM.
By copying the BIOS into RAM the system takes advantage of
the shorter access times of RAM. Only enable shadow RAM for
ISA bus address ranges that contain adapter BIOS.
Warning
Shadowing is only appropriate for adapter ROM. It must never be
enabled for adapter card RAM in these regions.

Cache

Enabling this option disables the processor internal cache, and,
if fitted, the external cache. There should normally be no reason
to disable this cache, it will result in a performance decrease.
Some old software which is speed sensitive may not work properly
with the cache enabled. This problem is uncommon, and this
option is provided as a safety net.

System Speed

This parameter allows you to slow the ISA bus to 8MHz.
This may be useful if you have an old expansion card that will
not operate with the ISA bus running at higher speed.
Only select low if you have a problem with an expansion card.
You can also use the
between high and low speed.
Memory at This parameter allows the memory address range from 15MB
15MB-16MB to 16MB to be reserved for use by memory on an ISA expansion
card.
Fixed Disk This option allows you to set the hard disk drive to switch to
Power Saving standby mode after a period of inactivity. The period of inactivity
Mode is adjustable from 1 to 18 minutes.
6/10 XEN-PC OWNER'S HANDBOOK
+
+ + key combination to toggle
CTRL ALT