Compaq 164SX - Manual (Page 25)

System Configuration and Connectors 2–5
Bcache Size Switches (CF0 and CF1)
2.3 Bcache Size Switches (CF0 and CF1)
The Bcache size switches are located at SW1 (CF0 and CF1), as shown in
Figure 2–2. The AlphaPC 164SX is configured with 1MB of Bcache during
production; the other combinations shown in Figure 2–2 (.5MB and 2MB) are for
other implementations.
Note: The standard motherboard (21A05-A0 for Windows NT and 21A05-A1
for DIGITAL UNIX) is manufactured with 64K × 32 data SSRAMs. An
OEM, however, can create an L2 cache in either a 2MB variation, using
128K × 32 data SSRAMs, or a .5MB variation, using 32K × 32 data
SSRAMs.
2.4 Password Bypass (CF2)
AlphaBIOS provides password protection. However, password bypass is provided
for system setup or startup when the AlphaBIOS password is unavailable.
Password bypass is disabled by default, with switch CF2 of SW1 in the on position
(see Figure 2–2). When this function is enabled, it disables the AlphaBIOS password
verification and enables the user to set up or start up their system without the
AlphaBIOS password. Password bypass also clears the password.
To disable this function and require a password, slide CF2 to the on position.
2.5 Fail-Safe Booter (CF7)
The fail-safe booter provides an emergency recovery mechanism when the primary
firmware image contained in flash memory has been corrupted. When flash memory
has been corrupted, and no image can be loaded safely from the flash, you can run
the fail-safe booter and boot another image from a diskette that is capable of repro-
gramming the flash.
For more information about the fail-safe booter, refer to the AlphaPC 164SX
Motherboard Windows NT User’s Manual.