I have netbook, similar spec, and similar problems.
I have two different cables, one is Prolific other is FTDI.
With one (not sure which) netbook can't even see VEMS, regular better notebook works 100% OK.
With another cable, netbook connects to VEMS but it gets disconnected from time to time, gets stuck from time to time and have hard time logging. I think netbook is to weak to do all that.
Regular notebook (Core i5...) works great with this cable also.
So... try better PC, if not, then try another cable.