All Games started to lag suddenly

[Notoriouss21]

All of my games started to lag suddenly i dont know maybe because there is to much trash on my pc but as i know i used to run all games on max and the same thing happened before but i decided to clean it up with Malware & himan pro and it really helped and i fixed all problems but now it seems that it wont help , here are my specs

Specs:
Case: Corsair Obsidian 650D Midi Tower Black
: 1x 200mm Front, 1x 200mm Topp, 1x Bak 120m


Motherboard: ASUS P9X79 LE, Socket-2011, KUN PC-PROD
ATX, X79, 8xDDR3, 3xG3-PCIe-x16, SLI/CFX, SATA 6Gb

Processor: Intel® Core i7-3820 Processor
Socket-LGA2011, Quad Core, 3.6GHz, 10MB, 130W

Ram: Corsair Dominator GT DDR3 1866MHz 32GB

GPU: EVGA GeForce GTX 680 4GB Classified PhysX CUDA
PCI-Express 3.0

Hdd:
1. Samsung SSD 840 Series 250GB 2.5" BULK
2. Western Digital® Desktop Green 2TB
SATA 6Gb/s, (SATA 3.0), RPM = IntelliPower, 64MB,

Blue-Ray:
Lite-On Blu-Ray Writer iHBS112
SATA, BD-R: 12x, BD-R DL: 8x, BD-RE: 2x, DVD R: 16
:
Intel® Air Cooling
for Socket-LGA201

XFX ProSeries XXX Edition 850W PSU
ATX 12V V2.2, 80 Plus Bronze, Modular, 4x 6+2pin P

USB adapter:
ASUS USB-N13 11n USB Adapter
PSP XLink Kai Support
: win7 64bit ultimate.

 

[J_E_D_70]

Completely reinstall gpu drivers.

Cleaned dust out?

Check temperatures and voltages with a program like OCCT.