Web Browser time out's

I seem to be having problems with web browser time outs when going to different web sites. I have checked everything that I could think of and all looks fine. Here is my stats.
4 meg’s coming in. Of which 50 to 60% used up
Signals running around -62db to -70db thru the network
Correction level running around 90 to 99 %, no noise that I can see.
Ping times thru my network to the edge router is running 5 to 11 ms depending on loading( worst case it 5 hops to the gateway)
cpu loading 30 %

I did make a change awhile back in “Connection Tracking” but Im not sure if this effected this or not.
Any thoughts?