[German]Users of the new Microsoft Surface Pro 7 and Surface Laptop 3 models complain about problems with the WLAN part. After waking up from its energy-saving state, the WLAN speed suddenly drops to 10%.
Users of the new Microsoft Surface Pro 7 and Surface Laptop 3 models complain about issues with the WLAN adapter. A user writes on Microsoft Answers on October 30, 2019:
Slow wifi after Instant On wake up
I just acquired a Surface Laptop 3 13.5” and I noticed that wifi becomes (way) slower after waking up from sleep mode. A speed test shows a decrease in the order of 90% (from 100 Mbps to 10 Mbps).
I am not alone (a couple of posts on reddit deal with this issue) and I think it affects all the new Surface devices with Intel Wifi 6. Is Microsoft aware of this issue? Because it makes Instant On feature completely useless if it costs 90% of wifi speed.
Note that I don’t have issue with Ethernet.
When the device wakes up, the WLAN speed drops from 100 MBit to 10 Mbit. The user is not alone, as the topic is also discussed at Reddit. Barb Bowman has, in response to a tweet, provided a list of the places found in this tweet.
the reports r growing in Answers forum, plus Reddit threads. https://t.co/ukYpwKX2Ad https://t.co/VecRsjE9pp https://t.co/PZySEv7smr https://t.co/v2l5gv3HU2 https://t.co/UdcgbUgWmV https://t.co/hAJabY1LJR https://t.co/dSOTn2p1eu
— Barb Bowman (@barbbowman) October 31, 2019
The attempt to quickly install an Intel driver might go wrong. Recently, in my blog post Caution with Surface Pro 7 Wi-Fi driver, I pointed out that Microsoft uses a specially modified driver for the Intel AX201 WLAN adapter. If you install an Intel driver, you may not get the previous Microsoft WLAN driver installed.
At reddit a user describes the cause of this speed drop: The new Intel AX201 adapter has 2×2 MIMO (twice the number of antennas for 2 times the WLAN speed if the router supports it). If the Surface device goes into standby mode, the Dynamic SMPS feature deactivates one antenna and the other antenna goes into low power mode. The error, however, is that after waking the device from standby mode, the second antenna is no longer activated and the other antenna remains in low power mode. This results in greatly reduced speeds and higher latency. The user describes two workarounds to avoid this:
Go to the hardware manager -> network adapter -> Intel AX201 -> Advanced -> MIMO power save mode -> Change “Auto SMPS” to “No SMPS”. While this resulted in the bug occurring less frequently, only changing the setting to “Static SMPS” (-> disabling MIMO) eliminated the problem entirely for me.
(Optional) Go to the Windows Settings App -> System -> Power & Sleep -> When my PC is asleep and on battery power, disconnect from network -> Change “Never” to “Always”
In the first workaround, Auto SMPS is disabled for the WLAN adapter, turning off the power saving. This results in higher power consumption, but prevents the speed drop. The second workaround is from the Settings page, where the network connection settings are adjusted.