Not to say it is limited to one MB. It can be larger (or smaller), but I just did not want to type that out.
Yes. This is probably the main cause for the problems.
There is one computer (laptop) with 3 GB of memory, and one machine (university) with 0.5 GB of memory.Physical memory on your machine is about 3 Gb and swap is about 2 Gb; so total virtual memory is 5 Gb not 0.5 Gb; not sure how you get 0.5 Gb.