PC Running Slow out of nowhere.

Computer Type: PC/Desktop
System Manufacturer/Model Number: Home made Desktop
OS: Windows 10 Pro. 64/ version 1709 Windows 7 Pro/64
CPU: Intel i7-6800K @ 4.3
Motherboard: ASUS X-99 Deluxe II
Memory: Corsair Platinum 16 gig @2400
Graphics Card: EVGA GTX 1070 OC
Monitor(s) Displays: Asus 27" LED LCD/VE278Q
Screen Resolution: 1920-1080 or 1280-720 HDMI
Keyboard: Das 4 Professional
Mouse: Logitech M705/MX Anywhere 2-S
PSU: EVGA Platium 1200W
Case: Phanteks Luxe Tempered Glass 8 fans/ one radiator
Cooling: XSPC/ Water Cooled CPU
Hard Drives: INTEL SSD 730-240 Gb Sata 3.0/
Internet Speed: 100 mbits
Browser: I.E. 11 default/Firefox/ ISP Time Warner Cable/Spectrum
Antivirus: Microsoft Security Essentials/ Malwarebytes Premium 3.0/ SAS
Other Info: LG BluRay Burner/ Sound system-KLipsch-THX/ Icy Dock ssd Hot Swap bays.