I used to design boards to environmental level 5.

Part of the testing involved putting the boards in an environmental chamber to temperatures of -40C (-50C for some special boards) and +80C (+85C for some special boards). Would they start up after an hour at either extreme was a basic test. (Emulating a night in a Finish tank, or a day in a Saudi helicopter.)

One particularly nasty test involved cycling from one extreme to the other and back again (within single digit minutes).

Condensation was a real killer until we insisted on conformal coating before testing (something that made rework much harder and so previously resisted - pun intended).

One of our customers does a lot of food transport. During summertime the warehouse got quite warm, and their walk-in freezer remained rather cold. They went through a lot of portable bar code scanners before switching to a different model!

(We also had to place a wifi access point within their walk-in freezer, because insulated metal boxes aren't particularly good at letting rf signals through. That also provided some challenges)

A previous employer of mine had a thermal test chamber for very similar purposes.

One day a colleague spilled coffee on his keyboard. It being a bombproof Model M or equivalent, he rinsed it clean under the tap and put it in the TTC to dry it out.

Which was a brilliant plan except that he forgot about it in there.

He was reminded, when the smoke alarms went off and the entire site got evacuated to the car-park.

Apparently, the keyboard, once retrieved, looked somewhat Dali-esque.

A few jobs ago I used to be an end of line QC technician. The medical products the company was producing for a client had to have their electronic performance tested by being immersed in a very strong saline solution, inside a lab incubator at a wide range of temperatures - from memory about 50c to -5 when they put in the fridge afterwards.

The rigs designed for this were supplied by the client, made of acrylic and superglue, with the PCB handling all the RFID stuff underneath the liquid reservoir. Even with conformal coating we used to lose one or two a week out of the sixteen or so that would be in use thanks to corrosion from leaking saline solution or the constant temperature cycling.

Not much fun when the custom PCB's came in at about £1000 and the client refused to change the design to make them more robust. Still, it was their money when the rigs broke.

Such temperature swings with high and low humidity is how CSR (now Qualcomm) used to test Bluetooth chips, running test software continuously. This does accelerated ageing of the package, leads, interconnects &c. Apparently condensation can get inside a solid chip package given enough time! But of course if the failure is after 10+ simulated years that's OK.

It wasn't enough to catch one nasty bug whereby booting the chip, it calculates a table for setting the radio on the 80 channels. Since things can warm, or cool, a load of extra entries are calculated, and the base pointer steps up or down the table as temperature changes so the radio still works. But not enough if it booted at -40° and it actually goes all the way to 80°C, when the table wasn't long enough...

It was a car company that found this one, in their testing of Bluetooth chips deep in the dashboard - as you said, Finnish winter to an hour's driving gets the whole car interior toasty....

Hot summers with rows of servers sat in a server room with barely enough airconditioning on a good day, let alone a bad one. It go so bad one year that the company had to open up all the doors to the machine room and hire massive fans just to try and get air circulating. The only warning we'd get of impending doom and hours of recovery time were one or two servers crashing with overtemp alarms about 15 minutes before the storage array would shut itself off (nowhere near enough time to shut down the remaining servers cleanly before that happened).

Didn't help we were a good hour away from the building the machine room was in, as were any DC engineers who could have warned us in advance. Yes, we comlpained about it all the time, and no, the company couldn't be bothered to spend any money to fix the problem.

A long time ago I worked on the top floor of a listed building that had been converted to offices.

Of course it turned into a sauna every summer, but staff requests for aircon were always declined.

And then we got new servers ... which turned themselves off on the first hot day.

Portable aircon arrived the following morning.

After that neat demonstration of where staff ranked, turnover increased considerably.

> turnover increased considerably

Financial turnover or staff turnover?

Then it wasn't a problem.

No urgency. The servers are down again ? Well, let's go for a stroll. Oh, you have urgent business to do ? I suggest you take that up with the CTO.

I've experienced this issue too. When i arrive at work on monday mornings, especially when it is cold or wet outside, it can take a couple hours for me to start working.

I had a piece of kit that that took ages to start if it was cold. The fans in the enclosures ran all the time, not just when the kit got hot, so if it was very cold I used to stick a tie-wrap into the fan blades to stop them until the kit got warm enough to start up.

I image that the HDDs couldn't spin up because the spindle bearing lubricant had got sticky with the cold.

There was most probably a minimum operating temperature specified for the drives by their manufacturer that was not complied with in this case.

I remember when, in about 1984, the design engineers got Compaq i386 PCs that had Western Digital 40MB IDE drives. After a year or so (i.e. just out of warranty), one of them stopped booting up. I was asked to investigate & found that the HDD wasn't spinning up because the spindle bearing had seized, the reason for this being that Compaq had ignored WD's fitting instructions and mounted the drive upside down, thereby putting the load on the bearing in the wrong direction.

With a gentle bit of hand rotary motion of the whole drive with it the right way up, I managed to free it and it spun up normally but there was no way without serious modification that it could fitted into the PC the right way up. Over time all of the other Compaqs failed in the same way.

I seriously doubt that the un*x boxen in the story were PCs with WD harddrives. The drives would have probably been CDC/MPI or the like.

Compaq's first 386 computer (the Deskpro 386) was released in late 1986. The hard drives were ESDI, not IDE.

WD's first 40 meg IDE HDDs were after they bought Tandon's hard drive manufacturing assets in 1988 (1989?).

In a past life I did user support and in the winter months I can't tell you how many people would complain their laptops wouldn't boot...always the ones who left their machines in the car overnight !.15 mins at room temp sorted them out. I guess these days with laptops using SSD's instead of spinning rust that sort of problem has gone away.

I worked for a company some years ago whose "server room" like a lot, was basically a broom cupboard. Well maybe slightly bigger, say a stationary cupboard.

It had a useless, tiny, aircon unit and the servers ambient temperature averaged out at 85-90C over the winter I was there.

I tried to convince them to get proper cooling but it always fell on deaf ears.

From what I head, come the following summer things crashed on a regular basis and they *still* didn't want to spend on cooling the room.

> "say a stationary cupboard."

Yeah, I hate it when cupboards move about regardless of their size.

We had a nice office with a great view, but the only problem was this was over an outside corridor. When it was cold outside we got cold feet, so we brought in insulation, and put a carpet on top. ( We did wonder why lowly minions were given such a nice office - every one else knew about the office). We complained to site services who said - there was not a problem - and we were wusses.

A director took over our office (and the ones next to it). The first cold day she complained the floor was cold - and whoosh site services were round "oh yes there is a problem". They found that water from the rain pipe from the roof was leaking into the space under the floor. When it was cold - it froze - and the cold flowed up to the floor.

It took them a few days to fix the leak - and a few months to replace all the insulation along the corridor - having to work from the outside.

As soon as manglement complains, there is immediate reaction.

Those at the coalface explain that there's an issue ? It's not a problem - deal with it.

Well, THERE's your problem. Even in the very early '80s, un*x was built for constant uptime ...

We had full-time Internet connections in the early '80s. TCP/IP itself went live in January 1983.

Back in the very late 20th century, I worked in an IT office on the sixth floor which was near the top of the main building. We would set the computers up with the software they needed and then cart them to their new location. In this case, the employee had a shiny new Viglen 286 to replace their old Amstrad PC - we set it up, moved it to the second floor and not long after we got a phone call to say that it had crashed. We went back down, reset the machine and poked at in to hope the problem went away. It didn't. After several crashes, we re-installed the old computer and took the new one back upstairs for testing.

It worked perfectly, of course. But we knew the user wasn't making this stuff up, so we left it on soak test for an entire weekend and it was fine. So, we swapped the computers back around again and of course the new one crashed again not long after, and we were swapping them back again.

The faulty computer sat in the sixth floor office and worked perfectly. The old computer on the second floor was working perfectly too, so we didn't think that there was something wrong with the second floor. This seemed frustratingly illogical.

Eventually the reason was found - because of the clapped-out nature of the building's heating system the sixth floor was slightly cooler than the second floor. Although it seemed unlikely that this temperature difference would cause a problem, we found that introducing just a faint waft of warm air from a fan heater was enough to make the PC crash. Cause identified, the machine was repaired and the employee got to enjoy their super-speedy 286 once more.