Why i get lag in online games when i spend 2 or 3 min of playing?

Throughout all of that, there is one thing you failed to mention. Your internet. Oftentimes, a bad internet connection can cause lag, not the computer itself. You should test your internet connection to make sure it is working properly. Other than that, you can try to defrag your hard drive. Seems like you tried everything but those two. Hope this helps.