With the VMXNET3 adapter and the the VMware tools installed the guest network connection will show up as 10gb, regardless of the physical adapter speed - this is expected behaviour, and rather confusing at first especially when you only have 1Gb uplinks.
The reason is shows up at 10Gb, is because this is the speed that it is connected to the vSwitch and this would be the same in a physical scenario - ie. the speed that you're connected to the switch at is the speed shown on the guest.
