This variety of problem is also difficult to name. In Alert!, a hardware conflict or hardware problem refers to a conflict between the existing hardware and some piece of software. In any known cases of two pieces of hardware conflicting, it is acutally a problem between the respective drivers, rather than the hardware.
An example of what Alert! refers to as a hardware conflict would be an application that works just fine until you try to run it on a Quadra or Centris machine. Another example would be a video board that doesn’t work when you turn on 32-bit mode.