Monitor troubles

[Matt]

I swapped a new monitor onto my computer, and while trying to make it look
better in SaX2, I screwed it up somehow. The monitor went black although
still on, so Irestarted. SuSE went through all the graphical logging stuff
where it initiates everything and puts "done" in green over to the side. But
when it gets to the login screen, it goes black. I tried logging in just
knwoing that the login is selected, and I can sucessfully log in. The screen
is still black, but I hear the KDE login jingle. I vaguely remember
accidentally setting the refresh rate to 150mhz at 1204x768, so I think
that's the problem. Starting with safe settings doesn't work, and neither
does putting my old monitor back in. The new one is an iiyama VisionMaster
450. How do I change the refresh rate without logging in? My distro is SuSE
7.3 personal. Thanks for the help with this, and my numerous other
questions. Someday I'll get this stuff.