Move Attachments to the File System
First go to the cPanel's File Manager and create an "attachments" directory in your site's offline root directory (the directory that File Manager defaults to) and CHMod it 777. Keeping this directory offline is good for security purposes (no one will be able to view attachments they do not have permission to view). Now go to the AdminCP, expand the Attachments list on the left side and click on Attachment Storage Type. Move your attachments out of the database and into the file system. Here is the path you will want to use, replacing yourCPanelusername with the username you use to login to cPanel:
Move Avatars and Profile Pics to the File System
In the File Manager, CHMod the customavatars and customprofilepics directories in your forums directory 777. Go to your AdminCP, expand the Avatars menu on the left side and click User Picture Storage Type. Move the avatars and profile pics to the file system. Here is the path you will want to for the avatars:
The URL should be:
Here is the path you will want to use for your profile pics:
The URL should be:
If you use something other than /forums/ for your forums directory, you will want to adjust the path accordingly. Also, be sure to replace yourCPanelusername with the name you use to log in to cPanel.
Move CSS to the File System
In the File Manager, CHMod yourvbulletin_css directory 777 (inside the clientscript directory of your forums directory). Go to your AdminCP, expand the vBulletin Options menu and select vBulletin options. From there select Style and Language Options in the drop down menu. Then set "Store CSS Stylesheets as Files?" to Yes and click Submit.
Check your gzip settings
Gzip is a compression technology that can reduce your site's bandwidth usage and by reducing transfer times, reduce server load. ASO already has gzip enabled on their servers (unless you are on Beta on Gamma) so setting gzip in vBulletin will double gzip pages, making them load slower, so you will want to turn off gzip in vBulletin. Here for instructions for everyone who is not on Beta or Gamma:
Go to your AdminCP, expand the vBulletin Options menu and select vBulletin options. From there select Cookies and HTTP Header Options in the drop down menu. Then set "GZIP HTML Output" to No, set "GZIP Compression Level" to 0 and click Submit.
Increase Cached Posts Lifespan
Go to your AdminCP, expand the vBulletin Options menu and select vBulletin options. From there select Server Settings and Optimization Options in the drop down menu. Then set "Cached Posts Lifespan" to 90 and click Submit. Other people might recommend setting this to 30 but my forums have it set to 90 and unless you are strapped for server space, setting it to 90 could not hurt.
Disable Template Name in HTML Comments
Go to your AdminCP, expand the vBulletin Options menu and select vBulletin options. From there select General Settings in the drop down menu. Then set "Add Template Name in HTML Comments" to off and click Submit.
Disable Search and Who is Online for Guests
Go to your AdminCP, expand the Usergroups menu and select Usergroup Manager. From there select Unregistered / Not Logged In. Set both "Can Search Forums" and "Can View Who's Online" to off and click Submit.
Turn on fulltext searching
Go to your AdminCP, expand the vBulletin Options menu and select Search Type. Set "Empty postindex and word tables?" to yes and click Submit.
Prevent search engine spiders from visiting areas of your forums that they do not need to spider
Create a robots.txt file with the following and upload it to your public_html directory:
If you use something other than /forums/ for your forums directory, you will want to adjust the paths accordingly.
Read more: http://www.vbulletin-faq.com/optimize-vbulletin-server.htm