Fun fact: by being able to access the payout statistics menu and knowing the machine's installation date it was easy to know which machines would be "hot". I have witnessed machines that paid out poorly for a couple years (+ a few million USD) but would hit regular jackpots near the end of their expected lifecycle.
I'm dubious that there is a per-machine fixed sum over a fixed time like this. Apart from the "progressive" machines that have a jackpot shared across a network of machines, I'm pretty sure that the payout percentage is just a statistical prediction, and that by law each result has to be independent of all previous payouts. Do you have a reference that you could point to that would confirm your understanding? The sources I've found say that each play is random: http://www.vegasslotsonline.com/faq/#random. You might be right, but I wouldn't want you or someone else to rely on this information if it's a myth.
I was actually working on the casino floor for a year and configured, repaired, diagnosed, and twiddled with these machines all day. It was a terrible job, but gave me something to do while hunting for my next IT adventure.
Other interesting observations: the machines based on Windows XP Embedded crashed all the time, the Linux ones were fine.
The Linux ones from several mfrs used APNG for the slot machine graphics. This was my first exposure to animated PNGs in the wild. (~2007)
The Linux machines loaded a kernel module at boot that was supposed to prevent/detect tampering with memory. Some also loaded their own audio driver stack which surprised me: wasn't ALSA or OSS. Very odd, specialized little machines. (Many were Pentium 3 with totally custom motherboards due to strange peripherals)
Progressives cannot legally be removed from operation until someone hits the jackpot. (at least in my state)
I'm dubious that there is a per-machine fixed sum over a fixed time like this. Apart from the "progressive" machines that have a jackpot shared across a network of machines, I'm pretty sure that the payout percentage is just a statistical prediction, and that by law each result has to be independent of all previous payouts. Do you have a reference that you could point to that would confirm your understanding? The sources I've found say that each play is random: http://www.vegasslotsonline.com/faq/#random. You might be right, but I wouldn't want you or someone else to rely on this information if it's a myth.