*SUMMARY*
(1) turn on all optional windows 11 updates, including all drivers and feature updates.
(2) use the wifi driver that Windows 11 installs automatically (for your realtek 8822ce internal card).
(3) do NOT USE Valve's driver (the one that you download off Valve's Steam Deck Windows Resources Page).


*I don't know how to fix the wifi problems on SteamOS or Windows 10

*I kept seeing on the internet that rolling back Valve's driver fixed the wifi on Windows 11 but it didn't work for me until i installed the optional updates. I see comments you YouTube channels that tell you to just roll the driver back saying that just rolling the driver back doesn't work for them. This might be why.

*Windows 11 will update your computer a bunch of times. Then it will say that it is done and there are no more updates. This is only true for the default set of updates. There's a way to turn on additional updates (you have to click things to tell it to do that). You need to take that extra step to get the wifi working.


*BACKGROUND*
I had "request timeouts" in my pings and 1-3s lag spikes in my games about every 3 minutes using the Deck (LED)'s internal wifi card. This happened on Steam OS, Windows 10 and Windows 11.

I fixed this by installing Windows 11 and updating it--INCLUDING ALL OPTIONAL UPDATES. I used the driver that Windows 11 installs for you. (I didn't install Valve's driver).

I had tried Windows 11 before and I did all the updates that Windows suggested. And my wifi card still didn't work right (with either the standard Windows 11 driver or with Valves' Driver). For some unrelated reason, I turned on the optional updates and then my wifi card worked very well.

So here is what I did.



*DETAILED STEPS FOR ENABLING ALL OPTIONAL WINDOWS 11 UPDATES*
Summary of Steps
start > settings > windows update (last choice on left-hand side) > check for updates/install all updates > restart a bunch of times > when it's done, go to windows update again, scroll down to "advanced options" > "optional updates" (in the second block of buttons) > (I guess I selected all of them. this included a bunch of drivers and all the feature updates.)

Only after I did all this did I install the Valve windows drivers for Steam Deck (but not the wifi one). Windows has optional driver updates for AMD and I don't know what they are or if they conflict with the Valve drivers but I installed the windows ones first and then the Valve ones.

I'll list all the windows updates I have in the first reply to this post.



*UNINSTALLING VALVE'S WIFI DRIVER*
Summary of Steps
win+x > Device Manager > network adapters > rltk 8822CE > right-click > uninstall device (also attempt to uninstall driver) > Action menu > scan for hardware changes >
right-click rltk 8822CE network adapter again > update driver > search automatically


Detailed Steps for uninstalling valve's driver
If you already had valve's driver installed, here is how you would uninstall it.
1. On your keyboard, hold down your windows key and hit the 'x' key.
2. A menu pops up. Find "Device Manager" and click that.
3. Another menu opens. Scroll down until you see the "Network Adapters" choice.
4. There's a little arrow to the left of that. Either click the name "Network Adapters" or that arrow. When you click it, the arrow will go from pointing right '>' to pointing down 'v').
5. Scroll down through your Network Adapters until you find the one that says
"Realtek 8822CE Wireless LAN 802.11ac PCI-E NIC"
6. Right-click it and select "Uninstall Device" from the right-click pop-up menu.

7. This should bring up a pop-up menu to confirm that you want to uninstall
the device. Mine had a blue-checkmark that said "attempt to uninstall driver".
Select that box also.
8. The "Realtek 8822CE Wireless LAN 802.11ac PCI-E NIC" entry will dissapear
from your list of network adapters. So go to the top of the device manager window
and select the "Action" menu (it's where the 'File' would be in a text editor--at the
very top of the window).
9. Select "Scan for hardware Changes".
10. Go back to Network adapters and the
"Realtek 8822CE Wireless LAN 802.11ac PCI-E NIC"
will be back.
11. I don't think you have to do this, but I right-clicked it and did the
"update driver" > "search automatically for drivers" thing.
(Windows should have installed its own driver when it scanned for
changes and found the card
12. If you did this right, you should be disconnected from wifi and be
prompted to find your network and re-enter its password.
This will prove that the old driver is gone.
13. If you want even more confirmation, if you right-click the
"Realtek 8822CE Wireless LAN 802.11ac PCI-E NIC"
and click "properties" > "driver" tab > "driver details" button
it will give you more information.
Mine says this:
Provider: Microsoft
Driver Date: 7/10/2019
Driver Version: 2024.0.8.108
Digital Signer: Microsoft Windows
(I don't think just having this driver is enough. I think there's some additional windows updates that made the driver work).



*MY PING RESULTS*
To show you how much better it works now. This is actually comparing the Windows Standard Driver to Valve's Driver after all optional Windows 11 updates were installed. But the results are similar to what I was getting with Windows standard driver before I installed the optional updates.

Windows Standard Driver
Packet Loss
Packets: Sent = 3939, Received = 3937, Lost = 2 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 15ms, Maximum = 1435ms, Average = 20ms
(This is about 2 lag spikes/dropped packets in like 20mins to an hour.)


Valve Driver
Packet Loss
Packets: Sent = 134, Received = 117, Lost = 17 (12% loss),
Approximate round trip times in milli-seconds:
Minimum = 17ms, Maximum = 104ms, Average = 24ms
(This is 17 lost packets in about 2 mins).