"https://superuser.com/questions/645918/how-to-run-google-chrome-with-nvidia-card-optimus" gives the answser. chrome disable nvidia gpu on optimus by default. The workaround in the post works for me too. Create hard links for browsers, and run it with nvidia by right clicking. At least I can see the it in the GPU monitor.
It should work, as I tested it with webgl and saw the fps difference.Here is the command for chrome. C:\Program Files (x86)\Google\Chrome\Application>mklink /H gpu-chrome.exe chrome.exe Hardlink created for gpu-chrome.exe <<===>> chrome.exe
This trick also works on firefox.