vsync?

Bangle.setLCDMode() or Bangle.setLCDMode("direct") (the default) - The drawable area is 240x240 16 bit. Unbuffered, so draw calls take effect immediately. Terminal and vertical scrolling work (horizontal scrolling doesn't).
Bangle.setLCDMode("doublebuffered") - The drawable area is 240x160 16 bit, terminal and scrolling will not work.
Bangle.setLCDMode("120x120") - The drawable area is 120x120 8 bit, g.getPixel, terminal, and full scrolling work.
Bangle.setLCDMode("80x80") - The drawable area is 80x80 8 bit, g.getPixel, terminal, and full scrolling work.

What does this all mean?
is 120x120 and 80x80 double buffered or not??
Or only doublebuffered is doublebuffered.. ?
What has 'terminal' got anything to do with the LCD mode?

I tested frame rate in the different modes:
80x80 = 33 fps
120x120 = 48 fps
doublebuffered = 67 fps
direct = 49 fps