Yes there is. The chipset in SP3 is different from the on in SP2.
If you search, you can see several problems with the Marvel Wifi chip in the SP3.
AVM has stated to work for bad wifiperformance with the mentioned Marvel chipset used in SP3.
Try the same test with another wifi accesspoint or router, probably your problem isn't there anymore
But this is a Scrolling issue. There is no load to the WIFI chipset at this Moment. I could deactivate Wifi after loading a Website and still have the unsmooth Scrolling situation.
In another Forum, i have found people who have exactly the same issue like me.
Please have a look: