FYI Bigfoot, I just checked the information my monitor gives me.

The optimal setting for a 24-bit 1920x1080 mode for my monitor is:

Horizontal frequency: 67.500 kHz
Vertical frequency : 60 Hz
Pixelclock: 148500
Polarity: +/+

But my monitor says the vertical frequency is 59 Hz. And the polarity is -/-

I checked monitor prefs, and the correct values are in there.
But it seems other values are used.

I hate to say this, but everything is ok with OS4.

Anyway, I just thought it was important to mention.