Is my XYZ video card supported in linux?

You probably mean X, not linux. There's a complete list of all supported chipsets and the name of the X server that supports it at: http://www.xfree86.org/cardlist.html If your card is in there then downloading the latest XFree86 distribution should work.

If it's not in there, there may be hope yet; http://www.precisioninsight.com is another group that makes X servers, specialising in cards that have proprietary chipsets which can't be distributed as open source drivers.

-- Contributed by Shadur.

Suse also publish some drivers that eventually end up in the regular XFree distribution anyway. Suse forks the XFree source tree, develops some drivers which the XFree team then merge back into the standard XFree distribution. You can either wait for the driver trees to be merged, or you can see if you can find something on Suse's site.