I've followed 4 different guides and done 2 complete kali reinstalls before posting this. I have a HD7970 video card I'm trying to use with Kali. After following the guides, I either get a black screen, or this error when running fgl_glxgears or fglrxinfo:

Using GLX_SGIX_pbuffer
X Error of failed request: BadRequest (invalid request code or no such operation)
Major opcode of failed request: 139 (ATIFGLEXTENSION)
Minor opcode of failed request: 66 ()
Serial number of failed request: 13
Current serial number in output stream: 13

I'm using this kernel: 3.18.0-kali1-686-pae

Can someone help point me in the right direction?