You can run speed tests at toast.net . I have Comcast also and have been complaining for years about slow speeds. A few weeks ago my speed dropped to 700 KB per second. After they worked on the problem for a week or so it went up to as high as 19 MB per second although normally it is around the more normal 5 MB per second. One advantage of that site is it tells you what is normal speed for the various ISP's.