I have got an ATI Radeon HD5770 (Gigabyte) graphics card and this card is very slow with native drivers.
If I install the FGLRX drivers (downloaded from the Radeon website), after a reboot, the Ubuntu GUI doesn't start.
On CLI, if I use "startx" command, XORG says, "No connected monitors".
I can't recover my OS and I have to reinstall.
What drivers work correctly on Ubuntu 16.04 LTS x64?
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