AMD reckons it knows why some Ryzen owners are experiencing
USB flakiness with motherboards based on a 500-series chipset. And with that knowledge, it plans to roll out a fix. This will come by way of a BIOS update, the timing of which will partially depend on the make and model of your specific motherboard.
This primarily has to do with users reporting dropped connections from external peripherals hooked up to a USB 2.0 port. For whatever reason, 500-series motherboards have been having issues in such scenarios, when PCI Express 4.0 is enabled in the BIOS. There was always the option of disabling PCIe 4.0—AMD also offered up a few other
potential fixes last week—but that takes away from one of the platform's main features.
Previous complaints suggested connection issues were more likely to manifest when the affected PC was under a high CPU load. Some affected users also found that switching a low-speed peripheral like a mouse or headset from a USB 2.0 port to a USB 3.0 port would alleviate the problem.
"We investigated the intermittent USB connectivity you highlighted. With your help, we believe we have isolated the root cause and developed a solution that addresses a range of reported symptoms, including (but not limited to): USB port dropout, USB 2.0 audio crackling (e.g. DAC/AMP combos), and USB/PCIe Gen 4 exclusion," AMD said in a statement.
AMD did not go into details about what exactly the root cause ended up being, but did say it is being addressed in the next version of AGESA (1.2.0.2), which is the microcode that motherboard makers tune their own custom BIOS firmware around.
If things go to plan, AMD will distribute AGESA 1.2.0.2 to its hardware partners "for integration in about a week." Given that time frame, users can expect beta BIOSes based on AGESA 1.2.0.2 from motherboard makers to arrive early next month.