Router Speed Test vs Device Speed Test.

I have the 1Gb package.  Running the Router Speed Test I get speeds of ~940/~940.  Running the Device Speed Test I get ~900/940.  Which speed test is more accurate?  I am guessing that the Router test only goes as far as my router while the Device test makes it to my computer.  If this is the case what slows down the Device test?  I have the Quantum router.