A few things:
Have a look at your addons & extensions and disable or even delete any that aren't completley necessary.
Type "about:config" into the address bar and hit return. Scroll down and look for the following entries:
network.http.pipelining network.http.proxy.pipelining
network.http.pipelining.maxrequests
Normally the browser will make one request to a web page at a time. When you enable pipelining it will make several at once, which will speed up page loading.
Alter the entries as follows:
Set "network.http.pipelining" to "true"
Set "network.http.proxy.pipelining" to "true"
Set "network.http.pipelining.maxrequests" to some number like 30. This means it will make 30 requests at once.
Lastly right-click anywhere and select New-> Integer. Name it "nglayout.initialpaint.delay" and set its value to "0". This value is the amount of time the browser waits before it acts on information it recieves.
Worked for me