The router and computers works fine, but for some reason when it tries to load web pages it would take a long time before it completes?
Try to update the firmware on the router first. Check and see if there is third party program running in the background that is eating up your resources. Also, check and see if the router is overheating or hotter than usual. It is better not to have the router on the carpet floor or inside of none air-flowing environment.