500 and color

[Ilwrath]

Some of the Magnavox Color displays have a "grayscale" or monochrome button.  I think they were for less eye strain, or something.  Anyhow, try poking at the buttons on the monitor.  It may be that simple.

Also, by RGB out, I'm assuming you're using the cable that goes from the Amiga 23 pin video -> db9 on the Magnavox?
(There were several other cables, including one from the Amiga 23 pin -> 3 RCA connectors, I think - if you're using this one, check and make sure you have all of those plugged in correctly.)

[Ilwrath]

Hmm... The only 23 -> 9 analog cable I have is the NEC model, which is molded and rubberized, hence I can't open it to check for you.  (It's one solid coated piece)

Here are the best pinouts I could find, though.  It looks like your cable is using the wrong ground, perhaps.  (digital ground - pin 13, instead of regular ground, pin 16-20)  Not sure if this would affect color, though.  (I suspect it SHOULDN'T, but then again, I'm far from an expert in my understanding of how video signals work.)  You will probably want to check out what is happening at the 9pin end of your cable, as well!

9-pin Video connector Analog RGB
(used by C=1084, Magnavox, etc. monitors)
  01 = Sync ground   
  02 = RGB ground   
  03 = Red Signal
  04 = Green Signal
  05 = Blue Signal
  06 = no connection
  07 = Composite Sync
  08 = no connection
  09 = no connection
 
23-pin AMIGA Video
  01-02 = External Clock + enable (usually unused)
  03 = Red Signal
  04 = Green Signal
  05 = Blue Signal
  06-09 = Digital signals (usually unused)
  10 = Composite Sync
  11 = Horz. Sync
  12 = Vertical Sync
  13 = Digital Ground (don't ground unless using digital)
  14 = Genlock overlay
  15 = Clock output
  16-20 = Ground
  21-23 = power outputs (+5/+12v!) (don't ground!)