I currently have a GTX 970, but after finding out about the 3.5gb of ram instead of 4 I've been thinking about getting an AMD 489x 8gb version. With all fanboy opinions aside is this a good move?
The only upgrade worthwhile is if your current card can't play your games at the settings/framerate you want and the new card could. So is your 970 holding you back? And will a 8gb 480 deliver where the 970 can't? If the answer to the first question is 'no' then that's that.
Agreed not a good enough increase to justify the cost. Only way I would do this is have a sale for the 970 for $200. The 480 at best only matchs the 980 so not that great of change. The 1070 at the very least is the power gain I would look for in an upgrade.
The only upgrade worthwhile is if your current card can't play your games at the settings/framerate you want and the new card could. So is your 970 holding you back? And will a 8gb 480 deliver where the 970 can't? If the answer to the first question is 'no' then that's that.