+1 for separate devices. Is it the initial website query that feels slow, or the entire loading process? Maybe try manually entering different DNS server addresses on your computer, if you're defaulting to letting the router handle DNS queries.
This is what I get on my business 50/10 connection pretty much 24/7. I'm using an SB6120 and a Netgear WNDR-3700 (v2) router, with DD-WRT flashed on it. Super responsive and rock-solid.