1) Open up your driver software, like AMD Catalyst manager and go to 3D Settings (may be under a Gaming tab)

Now set everything that you can to "Use Application Settings".

2) Underclock your GPU, download software available for your computer like MSI Afterburner (recommended if possible) or use AMD's OverDrive and set your Core Clock, Memory Clock, lower than they are and monitor your temps with HWMonitor or Afterburner and if your GPU temp goes above it's usual max temperature (Google your GPU temps to find it's idle temp and max temp) then increase the GPU fan (be warned if it stays on 80% or so it will burn out quicker) and if you're still hitting your GPU temp limits you can try lowering the power supply as well.

3) Lowering all settings, distance display etc.. All of this will influence CTD and can make or break your game even if you're managing 30+fps.

4) Revert back to default drivers, use the uninstaller in your Graphics Driver installer if it has it or do it manually. Also using some older/newer Drivers may work better for you. I'm running Catalyst 15.8 because Crimson drivers and the latest Catalyst version causes crashes for me.

5) Use Windowed mode with your screen's settings, may need to open Falloutpref in Documents/Games.

IF this helps anyone let me know. I still CTD but I've managed to minimize it as much as possible.