Although Windows 7 has been optimized a lox, the default Aero theme slow down older systems. Using a basic theme like the one on Windows XP is a good idea. It helps bring down memory consumption by a lot. Some even claim that the memory consumption can be brought down. to around 300 MB with no applications running. Change the mode by right clicking on the desktop and then on Personalize. Choose the Windows Classic Theme. To optimise things a little more, you can also turn off all the unnecessary visual effects. To do this, press the windows key + [Pause]. Then, click on Advanced system settings. Now, click on the Setting button under Performance and click the checkbox for Adjust for best performance.