Surface Pro 4 or Surface Book with a slow WiFi connection? Here is a simple fix

For those running a new Surface Pro 4 or Surface Book there is a very small subset of you with unique Wi-Fi access points that may be getting slow connections despite high-speed access.

Some users are reporting that their connection starts with high throughput but quickly dwindles down to a crawl. Microsoft support has confirmed a small driver setting that is causing this issue in their support forums.

"We have a known issue with .41 that results in low throughput with specific access points. The issue is specific to MAC layer aggregation (AMSDU over AMPDU) and only impacts a small subset of access points. We are working on a fix for an upcoming update. Until the fix is available, please update the registry key setting to work around this issue."

One example of this was from someone using a Comcast router, another with a Netgear Nighthawk X8 router and some general issues with 5 GHz connections. Luckily, there is an easy fix:

  1. Press Windows button. Search for Regedit. Open it
  2. Navigate to the following path: HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\mrvlpcie8897
  3. Find the item labeled "TXAMSDU." Double tap and modify the value from 1 to 0
  4. Restart the machine

We have not experienced these connection issues on any of our Surfaces, and it does not appear to be widespread either due to the specific nature of the MAC layer in question. Still, if you are experiencing a slow Wi-Fi connection despite having high speed access it may be worth taking the 30 seconds to enable this registry change. If you are not experiencing these connection problems changing the registry will likely have little impact on your current setup.

Source: Microsoft Answers (opens in new tab); via Windows Central Forums

Here's how to fix trackpad lag when scrolling on the Surface Book and Surface Pro 4

Daniel Rubino

Daniel Rubino is the Editor-in-chief of Windows Central, head reviewer, podcast co-host, and analyst. He has been here covering Microsoft since 2007 when this site was called WMExperts (and later Windows Phone Central). His interests include Windows, Microsoft Surface, laptops, next-gen computing, and for some reason, watches. Before all this tech stuff, he worked on a Ph.D. in linguistics and ran the projectors at movie theaters, which has done absolutely nothing for his career.

  • It seems like these two have a lot of problems, the way Windows Central has been posting about recently...
  • Actually, we're just posting more on it due to the higher profile of these devices. This issue is very specific and we have not experienced it ourselves. The help forums (here, reddit, MS) are not plagued with these reports. However, due to a fix being posted, it is worth highlighting.
  • The correct term to search is regedit.msc unfortunately MS had reverted back to their pre 7 search
  • Microsoft should have tested their devices on every single router configuration in the world /s
  • Nothing wrong in admitting there are issues with the new devices, my high end surface book with i7 16 GB ram has lots of issues. Unfortunately they don't have replacement stock and have put a backorder. Have to struggle thru all these issues until the replacement comes. Not cool for $3000 device, don't care if it's 1st gen whatever once it's on market all criticism's are fair if doesn't deliver given the market is trying to target.
  • Not any more than any new product. The problem with new products is that people have different scenarios which causes a product to behave differently than intended. You try to get as much out in testing, but the testers are usually tech people who behave differently than the general populace. Now that the public is engaged all those other issues begin to show up. A successful launch at this point is determined by the response time of said fix.
  • "a lot"... Not true, I d say normal issues on brand new products.
  • The Surface 3s have had massive Windows 10 issues but that was hardly getting any mention. Luckily they seem to have gotten better. But my digitizer did crash on me again last night.
  • This fix works for all windows devices(except phone). I think.
  • There's no mrvlpcie8897 folder in the registry of my Surface Pro 2, so probably not.
  • I'm curious if this is also the same "slow/crappy" wifi issue from the Surface Pro 3 that's been "fixed" many times but not really. If so, well, that took more than a year and praise Zuul. If not, I'm not even trying anymore. It's a lovely ~$1800 movie watching device.
  • I'll raise you. I bet my surface pro 2 wifi has been fixed more than your sp3 has. So much so I guess they stopped trying. ​
  • I fixed my Surface Pro 2's wifi once by uninstalling its driver in the Device Manager, I've never had to fix it again.
  • I think it worked with the April 2015 firmware, but I haven't had much luck since.
  • I take it you mean uninstalling and reinstalling?
  • I've had to resort to using the wifi driver from the May 2015 update. Rock solid on that one, otherwise wifi on any AC router I've tried doesn't work.
  • Not sure about this but my wifi issue with the surface book is after connecting to my wifi, a sec or two after traffic starts flowing, the wifi disconnects and the access point disappears from the active list and goes to manage(the area where you can remove known access points). Reboot if the books starts the process over again.
  • Try to just set wifi off and on again, this works to me (sp3).
  • Sounds eerily similar to my Yoga 2 Pro, not sure if the same fix does the job
  • Sorry might go out of topic The Surface pro 4 has two cons 1-No simcard port-A lot of tablets today have simcard ports, why not the pro 4? 2- No Usb 2.0-USB 3.0 should be better than USB 2.0, but does that mean we neglect 2.0? I like surface pro 4 but without these things, life is good but can be difficult at times.
  • You do realise usb 2.0 devices work in a 3.0 port right?
  • You want to call from a 12 inch device..It will look odd..
  • No, sim cards also allow you to have internet everywhere without WiFi. That's the main point
  • Hahaha the first complaint is legitimate, but the second is funny. Usb 2.0 works in Usb 3.0!
  • ever heard of USB SIM Card adapters?
  • It does. We've been having serious problems on 5 GHz on D-Link, NetGear and even Engenius. After changing this registry key all problems have vanished and performance has improves by at least 5 times. Most annoying were minute long drops in connectivity. All gone now. Why is this only now ... Surfacing ...?
  • Even with Western Digital wifi routers.
    HP Spectre suffers from this issue too.
  • At home and on the road I use my Lumia Hotspot as Access Point. At office, I use our Corporate Access Point. So both my SP2 and SP4 are only asked to use those 2 connections and have never had an issue with either Surface. But I will make this reg setting anyways while I have it in front of me. Note: My only bug with the SP4 is the already infamous video card driver crash. Ironically, I get more crashes with IE (scrolling) than Edge. Looking forward to the fix. Otherwise, SP4 is simply amazing experience.
  • All Surface devices have had slow wi-fi since RT. They're constantly "fixing it" and it never gets much better.
  • Well my Surface Pro 3 has had constant Wifi issues ever since I bought it, with the Wifi disabling itself randomly. My old £200 crappy laptop maintains a constant connection fine, while my £1000 surface pro 3 i5 (still paying it off) has never gone a while day without having issues. If I wasn't paying it off still I would ask for my money back, maybe the Surface Pro 5 will finally have working Wifi...
  • If you have the LTE version you sometimes don't know the wifi disabled until you blow through a ton of metered data.
  • Then keep LTE disabled when you don't want it activating itself
  • YES! THIS FIXED MY ISSUE!!!   Although this isn't a widespread problem, I'm nonetheless very grateful this was posted. Every one of our Surface Pro 3 and Surface Pro 4 devices were affected by this issue. I got a new Nighthawk X8 Router and the SP3/SP4 performance was abysmal - exactly as described in this article. The registry hack and a reboot fixed the issue immediately. Thank you again.
  • So the fix in this article will also work on a surface pro 3?
  • Yes.
  • Oh dear! another issue. I think I have to stick a little longer with my SP2 and postpone the upgrade this Christmas season
  • I think windows 10 is causing all the problems. The OS is not up to the correct standards utilizing the hardware.
  • Is Microsoft shitbrained? Why these fuckers release their products if they are so buggy and shitty faults in their hardware's controls. Listen suckers please launch products which has good performance and certified approval
  • So even after 4 generations, they still have wifi problems... Time to start using another chip for wifi and Bluetooth maybe?
  • I still feel like its a bit spotty and inconsistent. However my speed test this morning delivered exactly what I expect this device should be delivering.  
  • Your speedtest results make me cry as a U-verse user out in the boonies. :/
  • worked great, thanks dan!
  • Brand new i7 discreet gpu surfacebook. Cabled speed on all devices is 180 MBPS. iPads are all 150 wireless. New Surface book maxing out at 40 on a good day. Comcast 3rd gen Gateway, Lynksys router. May return - this is nuts.  
  • Couldn't agree more. Not a word from Microsoft (no pun intended). I think they can't fix it. The WiFi chip is Marvell 88W8897. Maybe this will help? (tried to add  a link but central didn't allow me.....). Google for 88W8897 and drivers can be found. I don't know. Microsoft just does not respond. "working on a fix". Come on...
  • Wow, this registry trick worked perfectly for my Pro 4! I'm finally getting decent network speeds! We have a Netgear Nighthawk X6, and with a router that expensive, I was pretty upset that 3G tethering from my phone was faster than our home network, at least on the Surface.
  • theres no T..... in my controlset... mine is also called controlset001
  • This didn't work for me:( at least for my Steam downloads... my speed test shows 150 up and down but my steam downloads are crawling always dropping to 0 every few seconds
  • The Windows Registry fix did not resolve the issues with my wifi connection, dropping constantly about every 4 to 5 minutes. It has to be my Windows Surface Pro 4 system since none of my other devices have issues with my home wifi. This is the 2nd Windows Surface Pro 4 system I have had since December 2015, just 6 months. I had to send the other back due to Touch  Sensory issues and Touch Pad issues. I have been researching the WIFI issues for 2 months now and have tried driver roll back, and driver updates for the wifi Marvel driver as well. Nothing seems to be fixing the wifi issue at this time.