how do i turn shaders on cause i go to menu turn them on go to play and they are turned off

type /lws <shadername>.inc and make sure shaders are turned on in the options section

yeah i turn them on then type that but it wont work like it turns off straight away

Your graphics card either doesn't support shaders, in which case you must buy a new one, or you don't have drivers installed.

What is your graphics card?

To find out -> start - run - dxdiag - display name

^^

That means your graphics card in your computer is not up-to-date or not powerful enough to support the graphics 'shaders'

how can i make my crap computer work faster with shaders??

If your computer can't display shaders then there are two things you could try.

Firstly, updating the drivers on your graphics card. This can be done for free from the website of the manufacturer of your graphics card (www.nvidia.com, www.ati.com, etc). This might give you compatibility with shaders but chances are that either it won't or it'll run slowly enough.

Secondly, buying a new graphics card and more RAM for your computer. Although this would cost, it would be more likely to get you shader compatibility. I'm not an expert in these matters though so I'll leave it for someone with more knowledge of the subject if they want to explain further.

your grafic card doesn't support shader sorry. . .