I am experiencing very weird behavior, to my knowledge this behavior was present ever since i got the machine (Possibly less bad on older bios revisions, it happens on the newer revisions i have tested). The external USB 3.0 SCSI over USB enclosure keeps disconnecting, originally seemingly random but i figured out the 2 scenario’s that trigger it.
Scenario 1: Hardware checks during driver installations.
I can trigger this manually at will on any Windows 10 build, it happens either during the hardware check phase of the AMD GPU Driver installation, or the initialization screen (Before you first click next) on my Intel LAN Driver installation. When this happens the drive disconnects most of the time but not always, if i trigger it to soon after the last time it will keep working as intended but if i wait a few more second i can always trigger it on the second attempt.
Scenario 2: HDMI Monitor goes to or from sleep (Not to be confused with the system going to or from sleep)
This one is the easiest for me to replicate trough remote desktop and only happens on the newer Windows builds which is why it took so long for me to really get issues with this bug as originally the cases where this happened was only during initial setup. When the monitor goes off the drive reconnects, and if i then cause it to go on remotely for example by playing media in MPC-HC or connecting to the session it will cause another reconnect. On older builds like Windows 2016 LTSB the monitor can go off just fine without this happening, but the way the monitor operates and the features in the AMD panel are different on this build since this is before the newer GPU driver implementations existed which explains the difference in behavior.
I have tried disabling USB Selective Suspend and different power profile settings as i always assumed this was my past solution (Turns out it makes no difference, i just did not have this outside of driver installs originally). I also tried both the AMD USB 3.0 ports as the ASMEDIA 3.1 port, both have the issue in the same way. Other USB devices are not noticably effected which might mean its something specific to USB SCSI. If i force the ASMEDIA driver instead of the Microsoft driver this will cause the external drive to drop USB SCSI compatibility and operate as a normal device instead but otherwise function without this issue eliminating any power issues. The problem here is that this also prevents the drives from going to sleep mode causing unnessesary wear and a lot of heat on the drives, so this is not a long term solution for me.
My motherboard is a X370 GAMING PRO CARBON previously running 7A32v1L but updated to the beta firmware 7A32v1NU with no differences. The controller of the external SCSI RAID enclosure is a generic one so i am unsure which one is used. (The enclosure itself is a iTEC MySafe USB 3.0).
I also tried multiple chipset versions including both the latest ones from the AMD and MSI websites with no differences in behavior. The behavior also happens the exact same way before chipset drivers are installed manually.
During the update of the BIOS all the settings got reset and i tested and succesfully replicated the issue on stock BIOS settings. Further tweaks such as messing with the xHCI handoff, Legacy Mode, UEFI/LEGACY, PCI, IOMMU and overclock settings did not make any differences.
To my knowledge Linux is not effected as i never noticed it happening on Manjaro.
If anyone has an idea what i can do to solve this, or can point me in a closer direction what driver hardware checks and display sleep mode have in common so i can find a more specific solution it would be much appreciated.
Summary
Motherboard : MSI Gaming Pro Carbon X370
GPU : ASUS Vega 64 OC (Air)
RAM: 2 sets of Corsair Vengeance LPX 16GB (Also happened on one set)
Windows 10 LTSB 2016 (Only during installs), Windows 10 1903 (Installs + Monitor), Linux seems fine
Behavior : USB SCSI enclosure rapidly disconnects and reconnects
USB Controller : AMD 3.0 + ASMEDIA 3.1 effected the same way
Not reproducable with the ASMEDIA driver indicating its not a power issue, this driver however does not properly support the drive so it can not be used long term.