I suspect it has to do with the automatic graphics switching in 15″ MacBook Pros so you could try disabling this in System Preferences. This isn’t happening to everyone who updates but I’ve had others tell me it’s also happening to them. If you choose to update PLEASE understand what you are doing and how to reverse it. Warning – Ever since updating to macOS Sierra 10.12 and the current 10.12.1, NVIDIA’s drivers are causing my Mac to kernel panic. Even if you’re confident about updating manually think before you do it, is it really necessary? Apple optimise macOS and update the drivers themselves to deliver the most stable, safe operating environment for your Mac.
I absolutely wouldn’t recommend doing this unless you know what you’re doing and confident in your ability to do so (that’s my disclaimer – if everything goes catastrophically wrong I cannot be held responsible).
All graphics driver updates come from Apple in macOS software updates so you really shouldn’t need to update them manually (the one exception is the Mac Pro which is the only Mac model to have user upgradeable graphics cards).
