The pixel shader is a component of the graphics card — it’s one of the ways graphics cards can make computer-generated images look so realistic these days. You’ll want to make sure that you have the latest version of the graphics card driver installed on your system, and that you’ve updated to the latest version of Microsoft’s DirectX software (use Windows Update from your Start Menu to upgrade DirectX). It’s also important to know if your graphics card can actually handle the high-end graphics the game will be expecting…if it’s an older system or a notebook, your system just may not be able to handle it…if you have a desktop and you really want to play the newest games out there.