I have the same problem,games no issues。but use browsers on Shopping website ofen get a crash，the website contain lots of videos show uploaded by buyers。keyboard and mouse locked,must reboot computer with power key.
I know you may not be happy with this, have you tried rating your ram at 2933MHz and move from there: https://www.amd.com/en/products/cpu/amd-ryzen-5-2600
I have built and used R7 1700, 1700X, 2700 using G.Skill Ripjaws V 3000Mhz ram 16x2 and ADATA XPG Spectrix D40 3000 Mhz 8x2. Stable at both 2933 and 3000. I have also replaced my WX4100 and WX3100 with both Sapphire 5500XT 8 GB version. I have a 550W Gold rated Antec True Power Classic and EAG Pro. Don't play games but run KeyShot and cad. Run Unigine Heaven, Superposition, SPECViewperf 13.0, OCCT for stability test. Using dual display, Firefox browser, Windows Mail, IronCAD and occasional render.
I am glad to receive your warmhearted reply。the screen freeze issue seems like be solved ，I disabled the EDGE browers hardware accelerate，then i visit Shopping website intermittently which cause the crash， from yesterday to now the issue not occur again。pardon my English，i am not good at it。
电脑型号 华硕 All Series 台式电脑 (扫描时间：2020年05月25日)
操作系统 Windows 10 专业版 64位 ( DirectX 12 )
处理器 英特尔 Xeon(至强) E3-1231 v3 @ 3.40GHz 四核
主板 华硕 TROOPER B85 ( Lynx Point )
内存 8 GB ( 金士顿 DDR3 1600MHz )
主硬盘 三星 SSD 860 EVO 250GB ( 250 GB / 固态硬盘 )
显卡 AMD Radeon RX 5500 XT ( 8 GB / 讯景(松景) )
显示器 HPN3603 HP 27qi ( 27.2 英寸 )
声卡 瑞昱 ALC887 @ 英特尔 Lynx Point 高保真音频
网卡 瑞昱 RTL8168/8111/8112 Gigabit Ethernet Controller / 华硕