If 75 percent of the game code can be split into subtasks that run concurrently, but 25 percent executes on a single thread, then regardless of how many CPU cores are available the best-case performance on a 4.0GHz Intel CPU would still only be 80fps. Imagine a hypothetical game where a single 4.0GHz Intel core takes 50ms to handle all of the calculations for each frame. The gist of Amdahl's Law is that there are always portions of code that can't be parallelized. But how much time does it actually take for each part of rendering a current frame? The answer is that it varies, and this leads into a discussion of Amdahl's Law. Jump to 144fps and each frame only has 6.9ms in which to get everything completed. For a steady 60fps, each frame has at most 16.7ms of graphics and processing time. That's because most games are still ruled by a single thread that does a lot of the work.įlip things around and think about each frame in terms of milliseconds. More importantly, the scaling comes mostly from clockspeed, with core and thread counts being less of a factor-especially moving beyond 6-core processors. Running at 1080p and low or medium quality, there's excellent scaling in terms of CPU performance, but 144fps is still a difficult hurdle to clear. Look at the CPU benchmarks in Assassin's Creed, Monster Hunter, and Hitman. Monster Hunter World also has difficulty getting above 120fps.
