Yes, drivers from Dell only. That applies to all your laptop's drivers, and it applies any make of laptop - you get drivers ONLY from that particular laptop maker's website.. Those from AMD are for retail motherboards with AMD video chip, or add-on AMD GPU cards, not for integrated GPU on laptops or factory-built computers.
I had a hunch you had downloaded the driver from AMD instead of Dell Support, too bad I didn't ask you earlier. Most likely explains why CCC stopped working.
Usually, Dell only shows the latest available driver so download & install that. Don't worry, it won't be exactly the same version you got from AMD and which has caused the CCC problem. On the Dell support site, enter laptop's "Service Tag" code which should be printed on the laptop's underside, it ensures that you are shown only the drivers that are relevant for your model.
To remove existing Catalyst driver, go here for instructions AMD: http://support.amd.com/en-us/kb-articles/Pages/AMD-Clean-Uninstall-Utility.aspx#
Good luck - - signing off.