I've just upgraded my Ubuntu 12.10 to the new 13.04 release (32 bit). I have a P4 @3.04GHz, 2GB of RAM and an AMD Radeon HD6670. After installing the new release I've restarted my computer and since then I've got the AMD Unsupported hardware watermark.
Since I've had some graphics issues (pixels jumping around) under 12.10, I've done the same thing as before, which has fixed the problem (changed the graphic display driver from the Ubuntu release to the proprietary one).
So I've done that again but, instead of leaving the proprietary one I've changed it to the Ubuntu driver (which I thought would be newer). I've restarted my computer and since then I can't see anything properly, just some random yellow bars flickering after the "ready to login" sound. I can't even login or anything.
This release (and the 12.10 after this one) is working great in my other computers (Asus EEE PC 1015PEM and Core email@example.com - 64 bits). I've just experienced such problems under the mentioned config.
What can I do to fix this?