Run Furmark, full screen 1080 res, 15 minute Burn in test. If your temps get much above 80C you most likely are in need of a repasting?
Of course open up the Fan covers and remove them and clean. I use a pencil or any object to hold the fan from spinning and blow it clean at the same time blowing the dust off your Heat sinks etc. Quit when you don't see anymore dust coming out the back. Cleaning should be a regular routine. I have a lot of dust in my area so I clean out the system monthly.
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