Depends on the actor, if it's one I'm familiar with then yeah, I usually do unless the character is something notable enough to stand out to me more.
Example:
Iron Man is Iron Man/Tony Stark to me, not Robert Downy Jr.
Everyone Christian Bale has ever played, he's still Christian Bale.
Vin Diesal is always Vin Diesal, with the exception of Riddick.
Matt Damon is always Matt Damon, Jessica Alba is always Jessica Alba,
And stopping now as there's no point in my randomly picking names out of my memory and expanding a meaningless list...