I found that one of the contact pins on the VGA (middle row 2nd from left) was pushed in which might have lead to no screen output. At the same time I found another mother board and purchased that and have fitted it and all is working now. Trying to replace the VGA connector on the old required minute solder techniques hence I decided to go for replacement motherboard instead.
At the end of the day it looks like the change to the registry was a coincidence to the VGA failing.
