The default, open source driver (which is used before you install the proprietary ATI driver) is not "flashed", but updated. What is a bit unusual here is that the open source driver should generally work for your card at this point without harsh words and a riding crop. Which means it may be something other than the driver, but we're going to go with that right now as a step in troubleshooting.
Instead of reinstalling (which I call the "Nuke 'em from orbit" approach), let's try to fix what you have. You're going to have to get cozy with the command line for just a bit. No need for fear.
When you boot, you probably don't see the GRUB screen because you haven't updated GRUB. So, just as your BIOS is finishing up, hold the space bar down to get the GRUB menu to display.
Choose "Recovery" and then "Root with networking" (or, if 11.10 doesn't have that option, choose "enable networking" first and then choose "Root")
Issue the following commands in order (I don't think you should have to, but if you get some complaints you may have to preface each of these commands with the word sudo):
(If you are asked "yes or no", answer yes. If you are asked for your password, type the password you set up when you installed.)
That will catch all the updates between October and now. There will be a lot, a lot of text will scroll by quickly and that will all be unintelligible to you. And it will take a while. Grab the beverage of your choice and relax.
Try to reboot and see if that helps. There may have been a bug that was corrected along the way.
If that doesn't work, get back to root with networking and do:
apt-get install fglrx && apt-get install amdcccle
If that still does not solve the problem, I have a couple of other things to try.