When testing games, CPU reviews tend to test reduced resolutions and quality settings with the highest-end GPU they have, as a means of highlighting the differences between the CPUs.
While there aren't any nefarious intentions on behalf of the reviewer, this approach runs into the following problems:
- People buying high-end GPUs are unlikely to be running at resolutions of 1080p or below (or at lower quality settings), and won't see as much (if any) performance difference between CPUs as what reviewers show.
- People buying lower-end GPUs are going to be GPU-bottlenecked, and won't see as much (if any) performance difference between CPUs as what reviewers show.
- Each frame being rendered needs to be set up, animated, sent to the GPU for display, etc., and like all workloads, there's going to be portions that can't be effectively parallelized. As such, the higher the frame rate, the more likely the game is to be bottlenecked by single-threaded performance, which is an area where Intel CPUs have traditionally been strong relative to AMD's. However, as frames get more complex and take longer to render, the CPU has more of an opportunity to perform that work in parallel, and raw computational throughput is an area where AMD's modern CPUs have been strong relative to Intel's. So just because a CPU has leading performance in games today, doesn't necessarily mean that will hold in the future as game worlds become more complex (and reviewers revisiting the performance of 2017-era AMD Zen 1 vs. Intel Kaby Lake in recently-released titles have already started seeing this).
In short, the way that reviewers test CPU performance in games results in the tests being artificial and not really reflective of what most end users would actually experience.
After all, a graph showing nearly identical CPU performance across the lineup and the reviewer concluding, "yep, still GPU-limited," doesn't make for an interesting article/video.
While there aren't any nefarious intentions on behalf of the reviewer, this approach runs into the following problems:
- People buying high-end GPUs are unlikely to be running at resolutions of 1080p or below (or at lower quality settings), and won't see as much (if any) performance difference between CPUs as what reviewers show.
- People buying lower-end GPUs are going to be GPU-bottlenecked, and won't see as much (if any) performance difference between CPUs as what reviewers show.
- Each frame being rendered needs to be set up, animated, sent to the GPU for display, etc., and like all workloads, there's going to be portions that can't be effectively parallelized. As such, the higher the frame rate, the more likely the game is to be bottlenecked by single-threaded performance, which is an area where Intel CPUs have traditionally been strong relative to AMD's. However, as frames get more complex and take longer to render, the CPU has more of an opportunity to perform that work in parallel, and raw computational throughput is an area where AMD's modern CPUs have been strong relative to Intel's. So just because a CPU has leading performance in games today, doesn't necessarily mean that will hold in the future as game worlds become more complex (and reviewers revisiting the performance of 2017-era AMD Zen 1 vs. Intel Kaby Lake in recently-released titles have already started seeing this).
In short, the way that reviewers test CPU performance in games results in the tests being artificial and not really reflective of what most end users would actually experience.
After all, a graph showing nearly identical CPU performance across the lineup and the reviewer concluding, "yep, still GPU-limited," doesn't make for an interesting article/video.