Try uninstalling the new game.

This year i bought an Alienware M14x R2 and was very excited for it. I enjoyed playing it for three months, and then the hard drive stopped working. After getting a new hard drive I continued playing on my Alienware for the past three months. All my games ran smoothly and I could play say a game like Planetside 2 with no lag. Then, I installed a new game and next thing you know I'm running Planetside with 30 fps and then a lag spike every 10 seconds that lasts from 1-10 seconds. This is happening to all my games like Minecraft and Kerbal Space Program. For Minecraft I used to play on far and now I can't even play on tiny! This has never happened before and I have searched everywhere for answers and haven't found one. Please help me. Thx