:-) I?m somewhat curious here, too. I *think* that as long as any file-write operations have completed (ie the tape isn?t still turning) there?s no risk of long-term data corruption - that is, there?s no open files as a modern hard-disk or SSD might have that need to be closed out. Of course, anything in RAM not written to tape (or floppy) would be lost, but maybe that goes without saying. But the question still has merit. Some power supplies electrically sequence voltages relying on the 120V to still be present even though the switch is ?OFF?, so powering down by pulling the plug out of the wall is a different (and possibly more stressful) operation that flipping the machine?s switch ?OFF?. My DEC Rainbow, for example, has a 2PST switch that powers both the electronic power supply (one pole) and the cooling fan (the other pole) and obviously it?s not brilliant to turn off the fan while the electronics are still running, but in that case the ?sequencing? works the same whether you throw the 2PST switch or pull the plug out of the wall. I suspect none of this applies to the VIC-20 - the power switch just disconnects the 120VAC from the wall in the same way that pulling the wall plug out of its socket (or flipping the switch on a power-strip) would do - but I don?t know this at all. Is that the case? I think the answer is different for almost any computer, so it?s pretty tough to answer generically, but it would be kind of interesting to explore all of the variations on this. - Mark

It is true that on any computers with disk drives, you should wait until the disk writing activity is completely done before shutting the machine off. In some cases, that is not just waiting for the drive light to stop flashing, but also waiting for any "delayed writes" that the operating system is going to do. On floppy drives, eject the disk, or at least open the door before shutting off, because some computers send a nasty spike when the power goes away. Therefore, in general, peripherals that can be independently controlled should be turned on before the computer is turned on, and turned off after the computer is turned off. On ST-506/412 type drives, it is good to "park" the drive before shutting down. The programs to do so are often seriously incompatible with IDE drives.

Mostly concur. I actually have 2 really nice pizza-box ?power bars? which are about the same footprint as a small CRT monitor. They have a single ?master? switch, so can be operated as above, and also individual switches for computer, monitor, printer, ? so that you can sequence all of the peripherals on before the computer itself if that is desireable. I?m pretty sure my TRS-80 recommended that, and the monitor it had would definitely cause a minor flicker in the lights at power-on, so it makes sense to me to get that transient over with before turning on the computer?s power supply. - Mark

On 3/16/22 13:37, Will Cooke via cctech wrote: If the question is being asked by a person of a certain vintage, I can understand the "why" of it. Gone are the days when you simply switched off the AC power when you were finished. Nowadays, everything from cell phones to Smart TVs go through a shutdown sequence. (My TV keeps playing the last ad before it goes silent). I remember, during the 1970s, when we were rolling out our microcomputer business software, it took a lot of reminding the operators that you simply didn't toggle the power switch when you were done. I'd suggested a "soft power" switch, but was overruled by the marketing people who thought that would only encourage customers to pull the AC plug. --Chuck

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