First thing to do is document what's going on. Install
Furmark This is a burn in test for you GPU,
Burn In test Hwifo64 hwinfo64 you can run the sensors only, you they will log you temps while you run burn in test. Run Furmark for the full 15 min burn in at 1080 full screen temps should not get much above 80C with Ambient temp 25C, Burn in on your CPU full 100% 15 minutes temp again should not get much over 80C
If your actualy getting over 90C under full load your most likely going to need a repasting same for GPU if it gets much over 80C
My GPU will get up to about 82C in 7 or 8 minutes then fluxuate between 80 and 82 for the last 8 minutes. My CPU never reached 70C in 15 minutes.
G752VY-DH72 Win 10 Pro
512 GB M.2 Samsung 960 Pro
1 TB Samsung 850 pro 2.5 format
980m GTX 4 GB
32GB DDR 4 Standard RAM
Z97 PRO WiFi I7 4790K
Windows 10 Pro
Z97 -A
Windows 10 Pro