[Info-vax] PWS 600au lost its memory: CMOS reverts to AlphaBIOS

[Ken Fairfield]

So I powered on my digital Personal Workstation 600au today and found
it
going through the AlphaBIOS boot checks, and the "splash" screen
showing
a PWS, etc.

This happened once before, so I remembered to go into the Setup,
choose
CMOS setup, and go into the Advanced CMOS setup were I could switch
back to the OpenVMS SRM console.  That done, I saved the new settings
(which was confirmed by a message), exited and powered cycled the box.

No luck.  I booted into the AlphaBIOS again.  I tried several times.
The one
thing I think is key is that the AlphaBIOS complained first about an
invalid
time.  I expect the battery for the BBCC (is that what it's called?)
is way dead.

So two questions:

1) Given the CMOS setup is non-volatile, does the system nevertheless
boot
into the (default) AlphaBIOS if the clock chip's battery is dead?
That seems
to be the symptom, but I'd like to know if there could be a different
cause.

2) Can someone point me to documentation one changing the battery, or
if it's integrated, the battery-backed clock chip?  Part numbers and
possible
sources would be much appreciated.

    Thanks, Ken