BDI Screen resolution & update rates?

Hi all,
I just installed the EMC-BDI on a PII-350. It went smoother than I expected
and I have, for the first time, seen the EMC window on the screen.
However, before I even try to find my way around in Linux and get EMC
running I have to change the screen resolution and or update rate because
the screen is very unstable and my eyes gets tired after just a minute or
two. So, where does one change those settings? I have found the 'Display
settings' next to the clock in the lower left corner but I can't find
anything about resoultion etc in there.
Thank you for your your time!
/Henrik Olsson. Sweden.