Interesting. Regarding the testing only touching limited portions of the address space, that reminds me of my early 90s vintage 486 (which I still have! :D). I

Interesting. Regarding the testing only touching limited portions of the address space, that reminds me of my early 90s vintage 486 (which I still have! :D). It would make the PC speaker tick as it counted out RAM. The first few ticks would be a little slow, then the rest would run quicker. It took me a few years to realize that it was slowly counting out the first 640K, then racing to the rest of the installed 8MB. I remember very well (this was the first computers I owned that I've been able to keep around... somewhere, lol) that there were exactly four "slow" ticks and then the rest were faster. I definitely have to find all the bits for that machine sometime - I just tried to reproduce the ticking sound with `beep` but failed, and Googling to figure out what frequency and duration the ticks might have had was perhaps predictably useless.