Hi, I had the same thing happen to my ASUS ROG G56JK, I was getting from 55c browsing to 80-90c load. After doing these my temps went down to 40c browsing to 60-70c load.
1. Go to your power plans, click on next to high performance, click change plan settings, go to advanced settings, click processor power management, from minimum 100% and maximum 100% put minimum 99% and maximum 99%.
If the step above helped with the temperatures, try creating your own power plan for browsing-purposes only with like 80% minimum and 95% maximum.
2. Your intake/exhaust might be somewhat restricted, so try blowing into them. This worked wonders for me.
3. Download "NotebookFanControl", this is what I use to control my laptop's fan. You can control the speed of your fan so It's not too noisy.
If none of the above helped you, then yes, you should disassemble your laptop, and fully clean it, from the inside as well as replacing thermal paste on the CPU and the GPU.