Thank you all for the feedback.
@Martin--cal: I should have seen the it's versus its mistake but obviously didn't.
As Rominara had pointed out, I thought more of "überlastet" concerning "overloaded" and not of "überfordert". I might concider the word for the first case (the processing unit or RAM reaching the top end of its available resource before all calculation steps are completed) but I think it is the wrong term for the second case. It AI software is after all not 'intelligent' enough or lacks common sense like humans have it, it is certainly not overloaded.
Describing the situation/failure with "... not designed to ..." as HappyMan suggested in #4 seems to be the best option.
As RTH01 mentioned, (almost) every machine nowadays has software included, unless it still solely works based on human or animal force and action like an old tractor. Whether a failure is due to a hardware or software issue, is imho not always easy to determine.
Anyhow, I wouldn't say that in either case the program/software or engine is overloaded.