Default monitor size [Linux]

I am using GRASS 4.1 under Linux on a 17" svga screen.
When I start a new monitor using d.mon, the resulting graphics monitor
is very small (about 3 x 3 "). WHen I streach the monitor size, I
usually get an EOF error when I try to display the next raster file. I
can use d.zoom & d.rast.zoom OK, but what I would really like is to have
my graphics screen larger. I have gone through g.help & the manual for
d.mon and looked at the tutorials, but have found nothing regarding this
presumably basic problem. Can I get there from here?

Thanks in advance,

  Bill Voigt