Greetings.
Most of the tools like the 3D model viewer are going to contain current models still being manufactured and sold.
For general specs and support information I would just start at: https://www.cisco.com/c/en/us/support/servers-unified-computing/index.html
From that link, you can drill down into the various categories of servers, including old M1 series, along with spec sheets, config guides, firmware/driver links, etc.
Kirk...
