John Carmack 注意到在 AMD Ryzen Threadripper 3990X 上因為 Windows 的 group limit 限制而造成效能問題：
AMD 3990 CPU scaling tests: Because of the Windows group limit of 64 CPUs, just firing up a lot of C++ std::threads didn't work great:
128 t = 67 s
64 t = 63 s
32 t = 84 s
16 t = 160 s
8 t = 312 s32 to 64 threads wasn't a big boost, and 64 to 128 was slower. However!
— John Carmack (@ID_AA_Carmack) April 11, 2020
但這點可以透過打散到兩個 group 改善 (workaround) 而提昇速度：
Setting the group explicitly let it scale all the way up:
128 t = 38 s
64 t = 48 s
32 t = 84 s
16 t = 160 s
8 t = 312 sNotably, because each group gets 32 hyperthreaded cores, 64 threads across 2 groups on an unloaded system is much faster because they are all alone on a core pic.twitter.com/Ip4OZsTXah
— John Carmack (@ID_AA_Carmack) April 11, 2020
然後順便看了一下目前 CPU Benchmark 網站上對於高階 CPU 的跑分數據「PassMark - CPU Mark High End CPUs)」，可以看到 AMD 最近真是香噴噴的，用 3950X (16C/32T，105W) 殺 Intel 目前最高分的 W-3275M (28C/56T，205W)，然後那個價差：
Intel 的 14nm 牙膏繼續擠...