Q: I am using Windows Virtual PC with Windows 7—how can I update the device driver to match the real NIC?

A: If you open Network Connections within the Windows XP virtual machine (VM) and double-click the Local Area Connection, the properties open and show you a speed of 100.0 Mbps, as the screen shot below shows.
xpvminwinvpc100mbps-Copy
It’s important to remember that this is a VM, and it sees emulated hardware. In this case, Windows Virtual PC provides an emulated Intel 21140 Ethernet device that runs at 100Mbps, so that’s the speed that is always seen, regardless of the true speed of the connected physical NIC. It is important to note, however, that this 100Mbps is just a label. In reality, the virtual NIC operates at whatever speed the true physical NIC is capable of.

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