The connection with your ISP is displayed in kilobits per second (kb/s), while your download speed is displayed in <b>kilobytes</b> (kB/s) per second (in most applications). So 150 kB/s is about what you would expect with a 1Mbs connection.
According to speed tests I have done and my bill I have about 1000 Kb/s download speed and 300 Kb/s of upload speed. Why am I topping out at 150 Kb/s when I am downloading a file?

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