I bought a pair of these desktops about a month ago listed below.
2018 Lenovo IdeaCentre 720 Desktop Computer, 8-Core AMD Ryzen 7 1700 up to 3.7GHz(beat i7-7700k), 16GB DDR4, 1TB 7200RPM HDD, Radeon RX 560 4GB.
I have been having laggy performance when scrolling web sites like Facebook, when scrolling down the page and coming to a video its blurry and takes a few seconds or longer to load. I looked into the Radeon setting on the PC's and both are the same and show the video cards only have 4096 mb of memory. I tried updating the drivers and get the message that I'm using the most up to date drivers. I provided a screen shot of my video card settings, please help if you can.