Lag causing big issues

I have over 700 hours. I love this game. after Ive been playing awhile, and sometimes right off the bat, the lag starts. The game freezes up and lags me around the map. Ive died and lost xp multiple times due to the game freezing up and then start running again at 800 mph. I know this isnt my PC, and I dont know what can be done about it, but it is frustrating.