Paged pool memory issues

When playing games via steam I occasionally get a crash followed by the error message.

failed to lock vertex buffer in cmesh dx8

According to the FAQ on steam this is caused by a lack of paged pool memory which is reserved for apps like direct3d.

To get round this issue its recommended that you remove a line form the boot.ini which unlocks the page pool memory. The line is /3GB /Userva=2900

Does anyone know where this line is in windows 7 or how I can unlock the paged pool memory as I'm finding the crashes are starting to interfere with my enjoyment of gaming.

Any help gratefully appreciated.

Interesting article with simular story
https://support.steampowered.com/kb_...5396&l=english

Thats the article I used to find the part about removing the line /3GB /Userva=2900

Try updating your graphics driver. That's often the problem.

Already tried various graphics drivers and found the same problem with all of them. I'm running nvidias latest whql certified one currently.