

If you have any more questions, don't hesitate to ask. I hope this gives everyone a better idea of what I'm up against. My last resort is to buy a dedicated LAN card but I'm not sure that will fix the problem and I really don't want the extra expense if I don't have to. On several occasions, suggested troubleshooters couldn't identify the problem which is of no help to me. I have gone through the adapter properties and Network and Sharing but I don't know what could be changed to resolve this issues without potentially making it worse. I suspect this is software related in that the network settings on the PC are different than that of the Surface. I have reset to factory conditions both the modem and router without any difference.

The speed issue on the PC presented itself as soon as I power cycled the modem, restarted and checked the speeds on all my devices using. The Surface gets the advertised 300 Mbps if it's connected wirelessly through an Asus RT-AC68U (AC1900 Dual Band 802.11ac Gigabit) router or wired to the router with an Ethernet 5e cable using a USB 3 10/100/1000 Gigabit Ethernet adapter. From it, I am expecting the advertised 300 Mbps, but I barely get 130 Mbps. The desktop PC is connected directly to the modem with an Ethernet 6 cable. The primary hard drives for both are 500 GB SSD and each system has 16 GB RAM. The startup apps of each are different but I don't think any would cause the speed issue unless there are some obvious gotchas that someone can suggest. Both run the latest updates of Windows 10 Pro using only Windows Defender for antivirus. The second computer is a Surface Pro 4 with a Marvell AVSTAR Wireless-AC Network Controller. This adapter has been "uninstalled" and "reinstalled" using the latest drivers from Intel. Its Asus PZ77-V motherboard has an Intel 82579-V Gigabit Network Connection built onto it. The "slower" desktop PC was custom built about 5 years ago. My ISP bumped everyone up from 150 Mbps to 300 Mbps on December 3. All that was necessary to do was turn off the modem (Hitron CGNM-2250) for 30 seconds and wait for it to establish a connection again. I suspect the network settings of the first are incorrectly configured to cause this degradation in speed but I have no idea what that could be. The second computer in wireless mode is still over twice as fast as the first one that is hardwired. An online speed test of one computer hardwired to the Internet has less than half the speed as another computer hardwired to the Internet.
