Why did remote desktop performance drop when switching from Windows Server 2012R2 to Windows 7?

Question

I have a desktop computer that I remote into on a regular basis. Prior to last week, the host OS was Windows Server 2012R2. Last week, I installed Windows 7, and I immediately noticed that the computer was more sluggish over remote desktop, especially when watching YouTube videos, which skip every half second or so for the entire video. Last night, I added an SSD and doubled the RAM in the computer (things I have been wanting to do anyway) and the performance still sucks.

The current stats of the RDP host:

• Windows 7 Ultimate
• 240GB Crucial M500 SSD
• 32GB DDR2 RAM
• NVIDIA GeForce GTX 560 Ti
• Intel Xeon X5365

The client computer was the same the entire time, but here are its stats:

• Windows 7 Ultimate
• 500GB 10K HDD
• 64GB DDR3 RAM
• NVIDIA Quadro K4000
• Intel Xeon E5-2687W

The internet connection on both sides exceeds 10Mbps upload and download. (I realize latency is the main concern, but I don't know how to measure this, and regardless it was the same with Windows Server as it is with Windows 7.)

I have tried changing the RDP performance settings on the client side from "Detect" to "Modem (56kbps)" but the "YouTube Test" still fails with an unusable, low frame rate video.

As per the suggestion from another Superuser question, I have tried both netsh interface tcp set global autotuninglevel=highlyrestricted and netsh interface tcp set global autotuninglevel=disabled, restarting the computer each time and re-testing. I did not see any difference in the performance.

My question: Why did the performance drop? My current theory is that the cause is the change in operating system. Is there anything else I can try to get the performance back to what it was?

Answer 1

Windows Server is an OS designed to be doing this. Windows 7 is a client based OS that has this feature for convenience.

In other words, a windows server doesn't use the same remote desktop server as windows 7 uses. In a server environment, you can have many concurrent connections, and there are many tweaks to enhance the performance, such as disabling Aero, where as in windows 7, it is much more oriented in brining the "known" desktop to the user instead. There are tweaks for Windows server to enable Aero on the remote desktop, and one of the things it does is decrease performance. I bet it is this what has the most impact.

Answer 2

The problem is the RDP (protocol) version.

Windows Server 2012R2 is the latest and greatest from the the RDP team and uses RDP v8.1 (server side). There are many fixes exactly in this area - video playback regarding encoding and decoding in H.264 format (which is faster and not laggy). See here: http://blogs.msdn.com/b/rds/archive/2013/10/31/remotefx-h-264-codec-improvements-in-windows-8-1-and-windows-server-2012-r2.aspx

Windows 7 (equivalent to Windows Server 2008) ships with RDP stack (server side) v7, there is a package to update to RDP v8 (I know it applies to Windows Server, not sure if it applies to clients as well), but there is no update to RDP v8.1.

From your description, your client is most likely Windows 8.1 and therefore can take advantage of the new features in the protocol with WS2012R2. With Windows 7, it automatically falls back to the RDP version on the host you are connecting to (v7 or v8).