Ok, so i still have the problem, but thought i would give others some fixes for the problem.

All of these have worked for someone.

1. Re-install/verify cache if you pre-loaded

2. Update drivers

3. Give the .exe admin rights and/or run in compatibility mode

4. Apply the beta patch of fallout 4. Click fallout 4 in steam -> properties -> betas

5. Disable steam overlay (reported to work by multiple sources)

6. Tweak fallout4.prefs into the following:

bBorderless=1

bFull Screen=1

iSize H={your resolution}

iSize W={your resolution}

If someone can give additional tips & tricks, would appriciate, as it is rather painful to hear others playing and not being able to even see the first loading screen yourself

this should fix your issue when crashing and then you can have normal setting's

Here might be a fix, if your using AMD, update the drivers to the latest BETA driver, then goto AMD control Panel (you may be using 1 or more Screen's) After going to the AMD control center, click Desktop Management > Creating and Arranging Desktops > 1 by 1 make each f them Primary.

Example make one primary, test game, doesn't work move on to next one.

Hope this help's, this has helped me and 2 others since i found this out!