Have you looked at the debugging help that is a sticky in the top 10 posts?
What kind of equipment are you using and what is your testing methodology? What do you mean by 'router is 300/867'?
It's one thing if you're coming at it with a computer that supports 1Gb line speed, using at least a cat 5e network cable, and are wired to your modem/router/wifi combo that also supports 1Gb speed. It is quite another if you are measuring while on wifi, connecting to your wifi AP with 802.11g speeds (54 Mb/s), and have 30 other devices on wifi as well all competing for bandwidth.