Except for any computation that can be tiled to use cache effectively so as to not be load-store bound, like FFTs, matrix multiplication, convolution, etc, whic

Except for any computation that can be tiled to use cache effectively so as to not be load-store bound, like FFTs, matrix multiplication, convolution, etc, which sound technical and not relevant to consumers, but actually underlie nearly everything that happens with images or sound on a CPU. I write optimized compute libraries for a living. Haswell really was an enormous improvement for real workloads (actually, more than 2x for some integer image-processing tasks due to three-operand AVX2 instructions eliminating the need for more moves than the renamer could hide in some loops). Is everything magically 2x faster? No, of course not. Are a lot of important things significantly faster? Absolutely.