Strange Radeon 4850 issues

[schtufbox]

My Nvidia GTX 260 recently died, so I put my old Radeon 4850 in my PC instead (can't afford a new card) , which I haven't used since this PC ran windows
It all works fine with the latest driver except one small annoying issue.
When I load any 3D game, the frame rate is beyond slow..it's like 2 fps at best...however, if I do CTRL+ALT+F1 to go to a terminal, then do CTRL+ALT+F7 to go back to the X server, the FPS jumps up to what it should be, and remains that way until I quit the game. if I load another game I have to do the same again

Any ideas how to fix this?

[schtufbox]

I should add, I have the same issue if I use the driver in the repositories too.

[schtufbox]

Got a new Geforce GTX550ti, the above is no issue with the Nvidia cards, so for me, problem solved.
However, the 12.6 AMD driver does fix the above issue if you have a compatible card...alas the 4850 only gets the 12.6 legacy driver..which STILL has the issue, in it's current beta state anyway.