I am confused about the difference between speed test results and actual speed. I recently signed up to fibre broadband which promises speeds of up to 40mb/s download and to it;s credit when I run speed tests on several sites it s around that, however when I am actually downloading files e.g downloading an ISO I get around 3.5 - 4 mb/s. this is still a great deal more that I got on regular DSL but I just wanted to clear up why there is such a difference.
The 40 Mbps is 40 Mbps per second, but Windows when showing file download speeds uses MB/sec which is Mega Bytes per second. Each byte comprises 8 bits, to 3.5 to 4 MB/sec is around 27 Mbps to 32 Mbps.
No disparity, just different units i.e the case of the b or B makes a big difference.