GPU and CPU Overclocking on my rig

[xbodrumx17]

I am clueless to the appropriate amount of Overclocking I can do with my rig. My rig can handle any game atm but a little boost couldn't hurt I figure.
For GPU overclocking I'm using MSI Afterburner
For CPU overclocking I'm using Intel Extreme Tuning Utility

Here are my specs. I'll try any combinations listed.
Thanks

Processor: Intel Core i7 6700K 4.0GHz (Unlocked CPU) (Quad Core)
Motherboard: ASUS MAXIMUS VIII HERO (Intel Z170 Chipset) (Up to 5x PCI-E Devices)
System Memory: 16GB DDR4 2666MHz Digital Storm Certified Performance Series
Power Supply: 850W EVGA SuperNOVA
Optical Drive: DVD-R/RW/CD-R/RW (DVD Writer 24x / CD-Writer 48x) (Internal)
Storage Set 1: 1x SSD M.2 (256GB Samsung 950 PRO) (NVM Express) (Extreme Performance)
Storage Set 2: 1x Storage (1TB Seagate / Toshiba)
Internet Access: High Speed Network Port (Supports High-Speed Cable / DSL / Network Connections)
Graphics Card(s): 1x GeForce GTX 1080 8GB (NVIDIA Founders Edition) (VR Ready)
Extreme Cooling: H20: Stage 2: Corsair H115i - 280mm Radiator Liquid CPU Cooler
Chassis Fans: Standard Factory Chassis Fans
Windows OS: Microsoft Windows 10 Home (64-Bit Edition)

 

[vapour]

MSI Afterburner is fine, slowly increase GPU voltage.
For CPU OCing, do not use software. You only need to increase Vcore voltage in BIOS and frequency slowly. Do realbench/Prime95 for > half an hour to see if your system is stable and monitor CPU temp and GPU temp. Usually if <85 degree under load, you are fine.