Listening to a recent Joystiq podcast I think the PS4 does install the complete game too. That said those times for the PS4 seem way off when you're installing games on it of the same size. I find it hard to believe its that fast.
According to here, Assassin's creed IV is 20GB. For it to install in 42 seconds, it would have to be copying to the hard drive at about 476mb/s. The Bluray drive is capable of - at max - 27MB/s. Even factoring in compression that would be pretty tricky.
On the other hand, I could be wrong. Kotaku seems to be saying the PS4 first installs the very basic files needed to run the game, then loads and installs files as they're requested. It's actually kind of brilliant, instead of Xbone's method of first having to block install all assets that the user can conceivably need before the game is finished installing.
Edited by grahamf, 28 November 2013 - 03:43 PM.
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