I am not able to use this resolution. The highest resolution is 1440x900 to set in game. 1 month old notebook and here comes the format :/
If I were you and you have an external HD at hand I would try to do a clean install on the external first and see if this helps, but before you do you could also create a new User in Users & Accounts, then login into that account and see if the lag is also there, this is done in a few minutes, won't say it will solve it but a clean User sometimes does make a difference, if it solves the problem you know you have issues in your normal account.