It shows that alot of your resources aren't being cached.
I suggest you do the following.
*Install cloudflare and disable it's rocketloader feature. It can help serve content as a cdn as well as help block attackers/bad bots.
*Install the htaccess found in my guide to help with caching, gzip & more.
*Try out vb4 supercharged.
*Optimize your images
*Where possible, add css sprites.
And last but not least, make a post here to help fine tune your server hardware/software.
https://www.vbulletin.com/forum/foru...-Configuration
If you need help with any of the above, simply look in my signature for the link to the popular guide.