Nikon D1X User Manual page 183

Custom Settings
Custom Setting 18: Monitor Off Delay
This item controls the length of time the monitor remains on
when no operations are performed. Note that increasing
the monitor off delay reduces battery life.
Option
10 s
20 s (default)
1 min
5 min
10 min
170
(continued)
No. Monitor stays on for (approx.)
CSM MENU
F18 Monitor Off Delay
10s
20s
1M
5M
10M
Ten seconds
T wenty seconds
One minute
Five minutes
T en minutes
10 s
20 s OK
1 min
5 min
10 min