Re: Doom 4 30FPS cap (?)
30 FPS wouldn't be a cap -- it's just the target framerate. This basically means that consoles will be "capped" by virtue of their hardware (since id will, presumably, design the content with that framerate in mind).
The PC can theoretically render however fast the hardware can. It's just the game will be locked at a 60 Hz tick, which means that every game process is scaled to run in synch with that. For instance, if your PC can only render the game at 30 FPS, every operation will be sped up by a factor of 2 to keep up the illusion. If the PC can render at 120 fps, the game events will be scaled down by a factor of 1/2.
Or at least this is how I interpret this.
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