Couldn't set 512x448 vid mode on Linux Red Hat 8

[Niddler]

[Arild@localhost Arild]$ zsnes

ZSNES v1.42 (c) 1997-2005, ZSNES Team

Be sure to check http://www.zsnes.com/ for the latest version.
Please report crashes to zsnes-devel@lists.sourceforge.net.

ZSNES is written by the ZSNES Team (See AUTHORS.TXT)
ZSNES comes with ABSOLUTELY NO WARRANTY. This is free software,
and you are welcome to redistribute it under certain conditions;
please read 'LICENSE' thoroughly before doing so.

Use ZSNES -? for command line definitions.

MMX support found and enabled.

Could not set 512x448 video mode: No available video device

Watch the last line. "No available video device" seems to be the problem... What can I do about it?
ANY help is of course appreciated, and you can mail me on arild@ekologik.se if you want.

Thank you!

[B;lly]

Is x running?
You need to type startx before you can run zsnes...

[Niddler]

Yes, X is running. :/

[B;lly]

weird...i've never seen that message before except for trying to start it w/o x...