That is the question. I almost never turn off the computer, but sometimes flick it off for just a second or two. Is this bad for it? Does it need rest? Thanks!
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If you want to reset your PC properly so things can ‘rest’, best practice is to power down then count to 20 Mississippi. This will give the various components that might store an electric charge to let that bleed out. This in turn will allow any remnants of code to die, allowing for a perfect restart
There is no difference between 1 second and 1,000 years to a computer provided the CMOS battery is charged. There is a difference, though subtle, between rebooting and a cycle of turning it completely off and turning it back on.
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Quick on-off cycles can be bad for some electronic components, but they don’t have to be long: a microsecond isn’t as good as five minutes, but 10-20 seconds is plenty.
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There are a few factors that play into this:
* Computers contains a lot of capacitors, and capacitors take some time to discharge fully, Power offs shorter than that may cause some charge, and thus data, to be retained. The exact time varies by a number of factors, but typically will be from 1 second to about 1 minute.
* DRAM, the main working memory for computers, will retain data stored in it for a period of time without power. To ensure accuracy, this memory requires frequent refreshes, typically on the order of every 50-100 ms for modern memory, however some data may be retained for 10 seconds or more.
* This is not to be confused with SSDs and other long-term storage, which does not require power to hold data.
These two are the most likely to cause problems, and are why hard restart instructions typically say to power off for a couple minutes. Such instructions will typically say something like “hold the button for 10 seconds then wait 2 minutes and try powering the device on”. The 10 second hold is to trigger the shutdown sequence, then the 2 minutes is to ensure the shutdown completes and all charges and data are reset. As hinted above, different devices require different times for a full reset, and the longest I’ve seen are about 5 minutes, though there is no reason that is a hard limit.
Quicker restarts are useful, however they may not fully solve problems with the machine. Such quick restarts will not cause problems, they just may not fix certain types of issues – in fact, most computer hardware has a reset button that will be a nearly instant power off and back on.
The final factor, which should not matter much, is that computers have a non-rechargeable CMOS battery to retain some data and maintain the clock. A power off while that battery is drained will typically cause loss of BIOS settings and the clock. The actual BIOS itself will typically survive, but user settings may be reset. These batteries will typically last for years as they have extremely low power draw – typically the battery will rust out before the charge is drained.
Most computers will need around half a second to turn off completely before restarting, to make sure everything is in a clean state. This is mostly due to capacitors (battery-like devices inside the computer that store a bit of power) needing to discharge.
If the system is restarted too fast, the system won’t be in a clean state and won’t likely be able to start up properly. For computer systems that are restarted using the soft-restart feature (e.g. clicking “restart”), this turns off all the major components within the system that need to be reset before turning them back on again.
Most modern computer systems will delay a restart if a problem is detected, this is why often if you need to forcefully shut down your computer using the power button, it won’t turn back on straight away if you immediately press the button again after the system turns off. This is done for the same reason: making sure everything is in a clean state.
What most people don’t realise is that literally everything, even the most well-engineered devices, are held together using proverbial sticky tape. In a typical device you have components from at least a dozen different manufacturers and all of them will have different specs: what always works to ensure everything is in a good state before turning the system back on is introducing a delay.
Source: software engineer for embedded systems, and I’ve come across Nvidia’s specs for their Jetson modules on this.
For example, for the Jetson AGX Orin (like a Raspberry Pi but a *lot* beefier), the main power rail needs to go below 100mV before the system is considered to be fully reset. The implementation guide (which tells you how to make a circuit board you can install the module on) gives 20ms as the time taken from when full power is removed and when the main power rail goes below 100mV, but with a 10% margin of error.
Ive had early 60gb ssds when they were first coming out and old pc parts from 1990 work just fine. There is a minimum time you must wait before all capacitors are discharged that state the pc is in would be considered the same as your 1microsecond – 5min analogy.
i don’t know what people are talking about here that things don’t work after 10 years. cause they do.
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