The answer depends on 800 MB of WHAT: low quality audio or high definition video?
9 minutes smartasses
7 HOURS
app. 25
There is no sensible answer to the question. A megabyte is a measure of computer memory whereas 120 minutes is a measure of time. According to basic dimensional analysis conversion from one to the other is not valid. For example, consider 120 minutes of high quality video and 120 minutes of low quality audio: there will be a huge difference in the memory requirements of the two.
That really depends a lot on the video's size and quality. Take a sample of a video in the desired quality, and look how many MB it takes, and for how many minutes it plays. From there, you can extrapolate. (1 GB = 1024 MB)
1 Gigabyte is approx. 1 million Kilobytes, so 0.8 Gigabytes
76 800 MB
9 minutes smartasses
how many minutes to make 1mb
7 HOURS
.82 GB is 839.68 MB(.82X1024)
app. 25
It depends on the quality.
around 300...
You are comparing two entirely unrelated units of measure. You might as well ask how many days there are in PI for all the sense it makes to compare minutes to megabytes.
100+ if compacted for the 2Mb and 800+ for the 4Gb
3:11 sec.