Hard Drive usage causing system lag [closed]

There is two built in diagnostics that may be helpful to figuring out your problem.

To get to them right click on Computer from the start menu and go to Manage. From there navigate to Computer Management -> System Tools -> Performance -> Data collector Sets -> System

System Performance will do a basic test that last one minute, System Diagnostics will do a deeper test but it takes 10 minutes. You start the recording by right clicking and pressing Start

Once you start the report it will show up in the Reports section, you just need to click on it to view it.

(If you get a graph with a bunch of lines instead of the nice report like the image above, right click on the report from the left hand window and choose View->Report)

From there it should flag anything that was out of the ordinary (high cpu, high disk usage, ect.) and it should help track down what is causing your slowness.

Run Resource Monitor and go to the disk tab and look which process causes high disk activity: