HBM 3D Stacked Memory is up to 9X Faster Than GDDR5 – Coming With AMD R9 390X and R9 380X 20nm Pirate Islands

[JEMC]

The new memory is cool and with AMD having access to it a year ahead of Nvidia could prove to be very good asset on its favor (and I say could because the 970/980 is faster than the previous cards while having a lower bandwidth than them).

But to me the interesting (and hard to believe) part is where they say that the 380X will be Nvidia's 970/980 competitor and 20nm like the 390X. Don't get wrong, I'd love if this is true, but then why did AMD looked for a liquid cooling solution for them?