I just found out about the existence of the Windows 9x hardware diagnostic tool "Hwdiag.exe" at the following website
http://www.windows-help.net/windows98/tune-19.shtml

It looks interesting.
It seems to pull together in one place a whole lot of diverse hardware info and display it fairly simply.

Problem hardware is shown in red.

This was only one of a list of tips shown here
http://www.windows-help.net/windows98/all-tips.shtml