1) Yes
2) Proof it does, at very low resolution, settings and sub 30fps frame rate
Gorath is right it isn't supported, but it does "run" the game with the latest drivers and tweeks done to the game to play as low as possible.
It seems unusual to me that an avid PC gamer would only have integrated Intel in their rig and not care about sub-30 fps in a shooting game (arguably the most important genre to have decent FPS).
I would not recommend it. I used to play a little of the first GW1 on an HD4000 in hotel rooms. It was playable but not great. I did significantly worse than if I was at home on a gaming computer.
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I don't know the player numbers but I'd hazard a guess the PS4 version is much more populated than on PC (guess).
A PS4 will play this game a lot smoother than an Intel 520.
There are (expensive) ways to use a KB/Mouse on PS4. This is the only reason I'm able to play console games because I cannot use a controller. Some people consider this "cheating" but to me this is no different than using a racing wheel, fighting stick or flight controller for their respective genres.
