does turning your computer on/off damage it?

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does turning your computer on/off damage it?


Saves money on the energy bill too (y)
It can wear out your hard drive booting up and shutting down your PC, but you can also fry your PC if you leave it running forever with insufficient cooling. So............ your choice.
Long as you have sufficient coling you will not fry anything.

Turning off you computer obviously saves energy costs however leaving it on can ensure safer operation.

When you turn off your computer the Hard Disk does some work which means moving of mechanical components, The hard drive must also 'park' before the power goes off, it must then activate when the power comes back on.

When the power goes off any virusus (if any) that made there way into your RAM or Hard Disk are more likely to be activated at the next boot sequence.

At the same time if the virus is present in RAM only and has no way of making it to the Hard Disk when your switch off it will delete itself and you will be safe.

If its on all the time its less likely these viruses will be able to initialise, However if you do install software which requires a reboot the same thing can happen.

Leaving you computer on also cause your Hard Disk to Fragment less BUT it also means your cooling fans will have a shorter life as they have a life in hours or rotations (about 5.5 years).
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I'd say turning it on and off is worse than leaving it on. The sudden surge of energy and change from cold to hot can't be good.

A lightbulb never just goes, its always when you turn it on.
For the average time in between upgrades that most people go by it won't matter anyway... the only components likely to go mid-term would be your fans, opticals and hard disks (i.e. the mechanical stuff) long term you'd be looking at a general breakdown in smaller components like caps on the board itself... in like 20 years...
I tend to find always-on systems are more reliable than booted-on-demand systems, one reason for this is that instability is picked up & solved earlier another is always-on systems tend to die catastrophically after a power cut/reboot/upgrade rather than fizzle out slowly. So the fact it's on 24/7 in its self leads to better reliability as you're more likely to get annoyed by occasional flakiness than if you boot it only when you want to use it.
My PC is booted up on demand as it can go days without anyone using, but it is ful of problems, mostly because of windows me.

However we also think the constant shutting down and booting on demand has caused damage to the fan bearings over the processor as its noisey now running normally but on start, especially after a few days not running, its horrific.

BUT my IMac will turn itself off after about a day in sleep- and always has done, and it works perfectly!

BTW i have AOL stuck on it at the moment ruining it and when I uninstall it, it does something for about 5 minutes and says its removed but its all there- if anyone can tell me how to get rid of this with out reinstalling the OS please PM me!
My Mum doesn't like my PC being on all the time, I turn it on most days and it's fine since Feb 04.

If you leave a PC running the RAM can get fragged up and it can do funny stuff, Server OS's have stuff written into them which allow them to run constantly.

Liam said:
If you leave a PC running the RAM can get fragged up and it can do funny stuff, Server OS's have stuff written into them which allow them to run constantly.
At worst RAM fragmentation adds a few ns latency onto retrieving data from the ram, also paging of data to swap (windows is highly developed in this regard) is like a partial RAM defrag anyway. The problem is more that over time programs that aren't fully debugged, or just badly written, can set flags and not unset them (or vice-versa) which leads to odd behavior and the longer a program is running, including the base OS programs, the more likely is it this is going to happen. Another problem is memory leaks, minor ones over time can build up into big problems. Both of these can be solved by periodic reboots (often required for patching of the OS and once a month is about the right amount of time anyway).
You will find that most servers do not run constantly, but are re-booted quite often. Where I used to work we had a weekly maintenance window where the servers would be patched, security fixes applied, applications installed, and the whole farm excluding the dc's restarted to avoid any memory leaks or dead sessions.

The servers may seem to be always running, but they have been restarted weekly which keeps them fresh and healthy.