Well, patch 1214 of the xorg-x11 package basically makes you unable to alter how much videoram your card has because the people at redhat were having too much problems with users setting wrong values. But should this be the case here ? I heard the patch might have other reasons to exist, but I'm not sure, so I decided to bring this under attention. Reproducible: Always Steps to Reproduce: 1. 2. 3.
The setting has no good reason to exist on the radeon driver, because all known cards are correctly detected. Its only purpose seems to be breaking configurations. If you actually have a case of a card where it's incorrect and no greater than 128MB, then a bug should be filed with X.Org.
Why no greater than 128 mb ??? I tried to find information on this and couldn't.
http://sourceforge.net/mailarchive/message.php?msg_id=13343102