[G4] G4- Apple Monitor Query

[Peter Webster]

Amazing List Deities:

I have a G4 500MHz Sawtooth, OS 10.3.9, 1 gig of SDRAM, AirPort Card,
external Firewire LaCie 120 GB HD and Maxtor Mini USB 160 GB HD and an
Apple 17" Studio (the flat one) monitor.

Sawtooth and Monitor were rescued from being thrown out (!)

They are resurrected and working great, but I have a question
regarding the monitor:

The monitor is attached directly to the CPU. using the cable that came
with the monitor. (There is another, separate, more complicated cable
with a brick and USB and other attachments that I never use.)

When the units power up, the monitor comes on very bright, then
settles to a less luminous display.

Adjusting the brightness does nothing, it shows as being at maximum.

Why the shift? It would be nice to have the brighter screen, and any
advice would be welcomed.

Thank you in advance for sharing your collective wisdoms.