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Ever since AMD released drivers for the new WDDM 2.2/2.3 for the new Windows 10 CU and FCU respectively, I've been suffering the same issue on my Radeon RX 580.
As the original poster said, it's especially noticeable with UWP apps, including those notifications that come up from the Action Center. I think the one that causes the biggest impact on my system is when I launch the Microsoft Edge browser; the mouse pointer stutters very badly for a few seconds while Edge is being loaded/rendered.
I've been trying to solve this thing for months now (since July 2017), trying fresh installations of Windows 10 along with every new driver that gets released but nothing works except if I use the Microsoft Basic Display Driver, but that's not a solution, of course.
My key system specs are the following:
Mobo: ASUS Crosshair VI Hero [UEFI BIOS: 3501] (Default settings without any OC made no difference) (AMD Chipset drivers up to date: 17.40 from December '17)
CPU: Ryzen 7 1700X @ 3.8GHz
RAM: 2x16GB DDR4 3200MHz CL14 (Samsung B-die chips)
Graphics Card: AMD Radeon RX 580 8GB Sapphire Nitro OC+ (Different OC settings made no difference)
Storage-> System: 1x Samsung SSD NVMe PCIe 960 EVO 500GB (I've tried different firmware versions as well as using Microsoft and Samsung drivers; no difference); Data storage: 1x Samsung SSD SATA3 850 EVO 1TB (latest firmware), 1x Toshiba HDD 5TB SATA3
PSU: Corsair RM850 Gold Plus Modular
This is not a problem with my system temperatures either. I've got a Corsair Carbide 750D Airflow Edition with 5x 140mm case fans connected directly to the motherboard to control them through PWM. The CPU has a mild OC of 3.8 GHz with a Thermaltake Frio Silent 14 CPU (140mm) cooler which keeps it under 30ºC at idle and at about 45~60 (depending on the game and the fan profile) while gaming with an appropriate custom fan profile.
My system was already assembled and working nicely with a budget card from another manufacturer. It did not start suffering from this issue until I bought the Radeon RX 580 and updated to the Creators Update/Fall Creators Update.
I really hope 2018 is the year when this problem gets solved.
The same issue remains with latest drivers 18.1.1.
When are you guys gonna at least acknowledge this problem?
Probably never. AMD rather knows about the error, but they are waiting for the end of product support. The error is not even on the list.
That's what I'm worried the most, the fact that they don't even acknowledge there's a problem that needs to be fixed in the first place.
Are you going to add this problem to the list, or we will pretend it is not there?
Exactly. The Same.
Look at those Reddit threads I made:
It's apparently Microsoft's fault, the only workaround here is to downgrade to Anniversary Update (1607) wich i'm actually using since the Creators Update mess.
But, you know what's crazy ? This also happens in Fedora (Linux)...
I think we're facing the biggest "bug" ever, and big companies are just ignoring it considering how big and complicated this bug is, and this whole thing is making a huge mess at Green side: https://forums.geforce.com/default/topic/1004600/geforce-drivers/all-games-stuttering-with-fps-drops-since-windows-10-cr…
But you will eventually want to look at Windows 10 LTSB as Anniversary Update Support is ending soon, LTSB is on 1607 too but has a longer support.