How do i make forum width fixed

[nbaphenom]

http://www.backstagegfx.com/forum/uploads/U929-1261598740.png
that black area i surrounded how do i make it a fixed width so that the sidebar can fit in place properly.

[nbaphenom]

Help .

[tome109109]

Wait you want it to be fluid you mean? Fixed is the version I believe you have. anyhow...Go to Styles in admincp then select it and find "StyleVars"

Change this accordingly.

Main Table Width (pixels or percentage) (This is the width of the table that contains all your vBulletin content)

Fluid is "100%"
Fixed is "850"