My device manager network adapters look like this. but there is no option or tab for deep sleep mode switching off. I dont know, whats wrong.
Unfortunately, it looks like hw issue with the network adapter, it's not even detected by OS. There should be at least an item with exclamation or question mark.
@sunberg Actually there is. @soamz What is the device ID of the Ethernet Controller under Other devices?
Simply you haven't the driver installed, almost surely because you downloaded the wrong driver. Your Ethernet adapter is there: other devices --> ethernet controller"