USB2 has a 480 Megabit/second maximum theoretical debit, not counting protocol overhead - this translates to 50 Megabytes/second maximum theoretical limit. In practice, it's closer to 40 Megabytes/s.Is the USB2 an issue at 50Mbps or 50MBps?
You said "50Mb" which is just over 6MB which seems pretty low to me since the USB2 controller can manage up to 60MBps so i assumed you meant 50MBps.
Um. Network cards don't usually handle offload for anything above TCP (OSI layer 4)... and everything below that is either always done in hardware, or provides negligible overhead.The major benefit to these cards is that they handle the buffer storage, encoding and decoding of data through the seven network layers.