From Windows Central:
Regarding actual performance, the Surface Go's single-core score (2,078) was essentially double that of the Surface 3's Atom processor (1,078) on Geekbench, with multi-core falling at a respectable 3,934. (up some from the Surface 3's multicore score)
For graphics, the Surface Go's Intel HD 615 (16,490) also doubled the Surface 3's Intel HD graphics (8,055) on Geekbench.
Geekbench 4.0 benchmarks (higher is better)
Device CPU Single core Multi core
Surface Go Pentium 2,078 3,934
Surface 3 Atom x7 1,078 2,777
HP Envy x2 (ARM) SD835 1,779 5,941
Surface Pro 4 m3 6Y30 2,854 5,350
Surface Pro 4 i5-6300U 3,319 6,950
Surface Laptop i5-7200U 3,725 7,523
Surface Pro 2017 i5-7300U 4,302 8,482
Surface Pro 2017 i7-7660U 4,513 9,346
Surface Book 2 13 i7-8650U 4,862 14,694
Surface Book 2 15 i7-8650U 5,036 14,237
Running at 100 percent CPU usage for 20 minutes straight in a 70-degree F (21C) room the Surface Go has no thermal or power-limit throttling at all. It ran consistently at 1.6GHz with no drops in speed the entire time.