Improve Performance

Speed up the performance of Path of Exile by disabling half of the CPU threads it's using.
Through much of Act 3 you'll find intensified magic casting and environment changes/effects such as the weather. This is all rather nice, except if you're running a lower end machine.
Of course, if you haven't gone through the settings and lowered your graphic detail, shadows and other settings then do that first. But if you've already tried that and performance is still struggling you can try doing the following.
For those of you on quad core processors (especially where each core has two threads, try disabling the odd CPU's. This will result in better resource management of your system and game. It will also help to reduce GPU throttling if you're overheating. In the case of overheating, you might notice everything is going rather smoothly until 20 minutes into game play when all of a sudden the game will slow down, becoming laggy, and frames become choppy.

To access the dialog above, pull up your task manager
  • One way to do it in Windows 7 (this should work on everything from XP to 8) is by right clicking the task bar and choosing "Start Task Manager".
  • Go to the processes tab.
  • Right click on the PathOfExile.exe process and select Process affinity.
  • Uncheck all the Odd CPU's as shown in Figure 2.
  • Hit ok, and then close the task manager.

If you're on a dual core computer and it only has 1 CPU thread per core then this trick won't help you. In the case where you have only 4 CPU's listed (dual core with 4 threads or quad core single threaded), it might only help you if you are having GPU throttling issues from overheating. Those scenarios are untested with our resources at the moment, though, anything is worth a shot when it comes to improving performance. Let us know your results if you find this helped you in any other setup or hardware configuration.
You'll need to do this each time you restart the game. There is a way to automatically set processor affinity on a per app basis. You can create a custom shortcut so that this happens automatically every time! CPU Affinity Performance Shortcut