Hi recently upgraded to GTX 1060 graphics card and game started to lag. I have all drivers up to date, what can i do ? 

T15K6 said:CPU: E8400
RAM: 4GB
GPU: 8600 GT
OS: Win7x64 Ultimate
With this specs surely can't run properly, can't run normally plus you used windows 7 64bit.,64bit much more hunger ram used than 32bit better you to use 32bit in your current system specs. Run only 1 application at a time. Defrag your system every month, or refomat it for fresh cleaner system.