Re: 4850 problems
I believe 10.3 is the latest, so yes he did.
Uninstall the drivers. Shutdown the PC and take the card out. If you've got onboard video use that to reboot into windows then shutdown again, if not just reset the BIOS.
Install the card again (if possible in a different slot). Make sure there's no dust clogging up the slot or on the pins on the gfx card. Install the 10.3 drivers.
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