Please, humour me… When you say “periodically updated”, how long a period typically elapses between performing each update?
How did you;
…if you didn’t have the Manjaro ISO?
It is highly recommended to download the latest Manjaro Installer ISO, as booting from it can allow repairs and/or recovery to be performed in many circumstances.
You might consider updating to the latest non-beta BIOS if the manufacturer lists one available on their site.
Regards.
Welcome to the Manjaro community
As a new or infrequent forum user, please take some time to familiarise yourself with Forum requirements, and the many ways to use the forum to your benefit:
Update Announcements
The Update Announcements contain important information and a Known Issues and Solutions section that should generally be checked before posting a request for support.
System Information
While information from *-fetch type apps might be fine for someone wishing to buy your computer, for Support purposes it’s better to ask your system directly; 
Output of the inxi command with appropriate parameters will achieve this (naturally, formatted according to forum guidelines) and will generally be more useful for those wishing to help:
inxi --filter --verbosity=8
or the short form:
inxi -zv8
- inxi man pages (Arch Manual)
Be prepared to provide output from other commands whenever asked. It’s equally important to provide as much actionable information as possible in your first post, rather than simply indicating there is a problem.