If these differ from desktop versions only by voltage/clock, isn't it super wasteful ? Do they really have so much surplus of these that it's worth to repurpouse them in notebooks or is it simply that these would cost same/more as the proper counterparts ?

Backstabak:

If these differ from desktop versions only by voltage/clock, isn't it super wasteful ? Do they really have so much surplus of these that it's worth to repurpouse them in notebooks or is it simply that these would cost same/more as the proper counterparts ?

Laptops have been getting desktop-class gpus for a few years now. It's really not a new thing. The shift happened with products like the GTX980M, which was soon after succeeded by a "proper" GTX980 for laptops. Ever since then, laptops have basically got the same gpus as desktops with some minor adjustments. However, theres always a premium to be paid for the mobile versions. They definitely cost more than their desktop equivalents.