tigervnc-server and AMD fglrx problems

Hello all,
I have a RHEL 7.2 machine running several tigervnc-server sessions. We were using the video controller on board with no special installation.

Once I tried to install the AMD fglrx drivers from the offical page things the vncserver will not start properly. The log file says:
Xlib: extension "GLX" missing on display ":3".

I have disabled the onboard video controller in the BIOS. I have tried removing and reinstalling tigervnc-server. I have tried reinstalling the fglrx driver to no avail.

I can login to the console and get a display just fine.

attached is the glxinfo output.

Any idea where to look next?

Kevin