im on a 4 mbps uncapped but my crapy isp only delivers bout 2.5 to 3 and its not even stable
4 mbps (millibits/second) or 250 seconds per bit is far too slow.
Netflix standard definition should be able to work with a speed of around 2 Mbps (Megabits/second). Note the 'M' for Mega rather than 'm' for milli.
For HD video you will need at least 8 Mbps, and for super HD you should probably allow 20 Mbps.
I hope this helps.
4 Mbps just means your streaming will be at fairly low resolutions. You need about twice the bandwidth that the service requires meaning your max streaming speed is maybe 1.5 Mbps.
Some day you'll realize that you need to provide actual information for anyone here to help. What EXACT service do you want to use? Which EXACT device are you using.
And no, 2-3MB is not enough for streaming high def anything (netflix, Sling etc).
They should state what their minimum is.