Do you know what the browser test is called or how to run it?
I didn’t run glxgears and I did run glmark2 yesterday but I stopped it half way through. If I remember correctly, the frame rates from the test ranged from 80 to over 1000 fps depending on the test but I have no idea if that’s good for the GPU or bad because I don’t remember the results I got on my old computer. If someone knows GPUs well enough, my old GPU was an intel HD Graphics 3000 and the GPU in this computer is an AMD Radeon R2 Graphics.
Also, I looked into Phoronix but it looks like it just benchmarks CPUs.