That shouldn't happen. I've tested several things, like upgrading video cards, upgrading memory, upgrading video card drivers, even flashing the m/b bios, and never got an activation request. So, it's strange that just updating drivers for the screen results in a reactivation.
However, please note that we don't control anything of the hardware detection routines, it's all done by the esellerate engine, which is a fairly widely used and well tested product. Our Addon Manager only reacts to what that library is telling it. And, even Esellerate have to rely on Windows itself to get informations about installed drivers. So, if Windows decided that an update of the screen drivers resulted in a change of other items in the PC config, which result in a general different hardware signature, Esellerate will take it like a hardware change, and our program will simply obey to that.
BUT, not all hardware changes necessarily consumes an activation. Some hardware changes, even if the present the activation request windows, might still be considered as "minor". So, you might only have the small annoyance of having to reply "yes" once to confirm the activation on the new hardware config, but it's not certain you really consumed one of the 6 available.
If you want to be sure about this, you can email me or PM-me with your Order N., and I can check how many activations you still have left. And, it will be absolutely no problem to give you an additional one, even in the case the hardware change was detected as a major one.