OT: My NEC monitor seems to be getting darker. Brightness controls are maxed out...

Expect about two years of use from a top-tier display before noticeable degradation of the display brightness.
Unfortunately, there isn't an easy way around this. Maonitors wear out; the push to create bigger, brighter monitors means that e-gun voltages are increased and that phosphor wear increases accordingly.
I ahve to re-profile my three-year old Trinitron diplay twice a month to maintain reasonable color consistency due to phosphor aging.
If your monitor has all the controls on "soft" buttons on the front panel, not real "pots", you may be hosed though.
It sounds like this is a typical 'high voltage' problem, that is, that section of the electronics starts going bad.




