Ok I was working on warcraft 3, basically the game increases the gamma (due to an internal setting on it) and would normally reduce it again on exit.
After the crash the gamma on my desktop is too high but also cannot be adjusted, some external setting stuck somewhere.
If I go to the nvidia panel and select "adjust desktop colour settings" "other applications control colour settings" is selected, if I choose "use nvidia settings" then my desktop reverts to normal but of course this stops games adjusting the setting.
So my question is can this situation be recovered if so and how? loading the game again and exiting does not recover the setting.