I agree that they can be powerful but I guess, as always, it doesn't apply in the general case. For example, AFAIK hw prefetcher runs at 32B or 64B per cycle wh

I agree that they can be powerful but I guess, as always, it doesn't apply in the general case. For example, AFAIK hw prefetcher runs at 32B or 64B per cycle which basically means that you're only going to see a benefit from it if the code you're running is CPU bound, no?