Scenario 1: Yes. But remember, the laptop is also connected to an adapter because it never needs anything more than 50V which means even if you are not connected via an AVR, if current goes up beyond 220V, the laptop is less likely to burn. The adapter WILL or MIGHT burn.

Scenario 2: Yes the AVR's fuse will blow but there is also a possbility for an adapter burn out. AVR 's may not be able to handle sudden surge spikes of bigger proportions. Surge protectors give better protection from lightnings. It's still better to connect your laptop to a surge protector than an AVR alone.


Scenario 3: This is where the AVR serves its purpose.