Chrome's GPU sandboxing is more aggressive, so it's probably performing extra copies. GPU round-trips (think synchronous operations like 'copy the result from t

Chrome's GPU sandboxing is more aggressive, so it's probably performing extra copies. GPU round-trips (think synchronous operations like 'copy the result from the GPU back to CPU memory) also end up being slower due to the delays introduced by bouncing things between the page and the GPU sandbox.