On January 14, 2015 at 14:14, Ernie Gilman said...
You may not agree with me about anything, but haven't we all learned at this point that asking questions "without getting into specific models, just general reasons why," results in no specific answers, just lists of the millions of possibilities?
This approach is easy for the person asking, because he doesn't have to think about any of the details. (Note the details already mentioned by others.) It puts the burden on those offering their time for free to answer the question: they must spend their volunteer time trying to beat details out of the asker so they can help. Let's extend the benefit of the doubt and say this is a reasonable approach to getting information: it's terribly unfair to anyone who wants to help.
In general I would agree with you but in this case the router model seems more or less trivial. Unless the router is defective (and that can easily be the case) it should not make a difference. And since the OP said he "Tried 2 other routers with same issue" it does not rule out a defective router but the model number most likely would not tell us anything at all. That is also why all the questions dealt with the other variables.
-----
to the OP a wireless router connects many things together. So first and foremost there can be a defective (or not) device that is spamming (or using) the bandwidth (BW) and that reduces the available bitrate (BR) for other devices. So for example if we have device A, B and C that are wireless and device D that is wired and there is a massive transfer from A to B happening , that would affect C that is connecting to the internet (speed test) but might not affect (as much) D
second, like others posted, sometimes a device itself can be an issue, now trying several routers would most likely mean it is not a router issue, but the device you are testing with might be, have you tried the test with different wireless devices as well?
thirdly what wireless is being used can affect things. For example 802.11b has a max of 11Mbps so you would never be able to have a device that is using it hitting 75 Mbps on a speed test
fourthly wireless uses RF and so the BR available will depend on many factors which is why we always talk of maximum BR (best conditions), anything that degrades the signal (such as distance, electromagnetic interference, blockage...) will also degrade the BR a device can receive at a given location
and lastly (for completeness- though I doubt it is your issue since they are off by default) some routers (and here a model might be a bit interesting) offer QoS (quality of service) options that can be set-up. What that means is that it will prioritize traffic depending on the rules you give it (think of it a bit like a bus lane, carpool lane, fast lane... on a highway where those vehicles can go faster on those lanes than the rest), some of the more professional devices under QoS could also have a max BR setting that can be activated (i.e. in a restaurant you might not want Bob to hog all the BW and so screw Joe that wants to check his e-mail)