Thanks, Borisz. I did find those posts, but I took that to mean that it's the temperature that the chip itself runs at if the rig is at normal room temperature.
Grout makes a very interesting point about the correlation between the two temperatures, and I guess I suspected as much. One seller was saying "Well, the operating temperature is 40-50C, and even in the summer, garages won't get that hot, so you should be good". But if Grout is correct, and it would makes sense that he/she is, then the seller either doesn't know what they're talking about or they're just blowing smoke up my ass.
Still though others have rigs in garages, right?
Ok, well I guess a lot of seller are just re-sellers and not actual manufacturers of equipment. Hence they don't know the exact specs. I was always wondering why there is no information given about operating conditions, normally it has to be given for every electronic product. Not even manufacturers give this info sometimes, however they were ought to test it! Just to set it clear,
ambient temperature = air temperature of the space where the miner is
operating temperature = temperature to which the miner heats when operated (this can be surface or chip etc. temperatue, depends where the manufacturer measures, if at all)
And of course there is a pretty much direct correlation between ambient and operating temperature, although it depends on other factors as well e.g. airflow, I thought this was clear from the start.
I am not even running my desktop PC much when temperatures are close to 40C and I would advice against running a miner under such conditions. As per the previously mentioned article says, the miner heats to about 42C if the room is at 25C. This is kind of a normal operating condition for electronics. It is probably safe to go until 35C, just like with an S3, however higher temperatures will lead to failures more likely.
Alternatively you can increase the air flow to cool the miner better. Where are you trying to operate it? Don't you have e.g. a basement or something similar?