PC on or off??

[goodone]

This is not really a security issue, I came across this discussion and I decided to share it with you guys. I really want to know what you think.

This is about whether turning your PC off or leaving it on 24hrs will wear its components. I don't know what to believe, so that is why I would like to hear what you guys have to say about this. So do you think it harms your PC when you leave it on 24 hrs a day or when you turn it on 5 or 10 times a day??

[Dan]

Indeed, Computers produce heat. If you have the hot water tap on over your hands for over 2 minutes it will hurt, if you didn't have any nerves your skin would be damaged.

It's the same with computer parts, thermal paste on the processor only lasts a few months before it starts to disappear and the more a computer is left on the more the thermal paste wears away and wears away the processor.

[Cassie]

So are you saying that on and off lots of times a day is better?

I have always left my computer on for sometimes 17 hours a day because that is what I often work with just half an hour here and there for food, calls of nature etc. So on the few occasions I leave my computer (I often eat at the computer too) should I really switch it off - or hibernate it - or power down or something.

[black-dog]

Indeed, Computers produce heat. If you have the hot water tap on over your hands for over 2 minutes it will hurt, if you didn't have any nerves your skin would be damaged.

It's the same with computer parts, thermal paste on the processor only lasts a few months before it starts to disappear and the more a computer is left on the more the thermal paste wears away and wears away the processor.

One word.

Servers.

[Dan]

One word.

Servers.

Servers have sufficient cooling, even so most servers can die down as well as computers.

After working with servers for a few years, the amount that die down faster than computers is large. Even as you will find.. servers need rebooting plus they have alot of air-space inside them not mentioning 2U chassis's generally have 4 fans in the middle making cooling a priority-point.

[Cassie]

So any chance of answering my question ?

[Dan]

Sorry Cassie,

I would Hibernate it but switch it off at night. Not only does it save power etc etc (And I'm not one for Global Warming and stuff) but it will also save you needing to replace hardware in the upcoming years

[black-dog]

Servers have sufficient cooling, even so most servers can die down as well as computers.

After working with servers for a few years, the amount that die down faster than computers is large. Even as you will find.. servers need rebooting plus they have alot of air-space inside them not mentioning 2U chassis's generally have 4 fans in the middle making cooling a priority-point.

True, but the average server is also generating more heat. But let us assume that a server, like a desktop computer, has a normal operating temperature and that that temperature is not being exceeded. It always used to be my understanding that it was better to keep components at a constant temperature rather than subject them to the thermal shock of continual heating and cooling. If the current thinking on this has changed, I'd like to see references.

[Dan]

True, but the average server is also generating more heat. But let us assume that a server, like a desktop computer, has a normal operating temperature and that that temperature is not being exceeded. It always used to be my understanding that it was better to keep components at a constant temperature rather than subject them to the thermal shock of continual heating and cooling. If the current thinking on this has changed, I'd like to see references.

I'd like to see references that your statement is true before you proceed to undermine on my comment. The only processors that can run without thermal paste are P4's. Thermal paste not only controls temperature but controls the way a computer cools down and is generally the only part in a computer / server that gets realistically hot by stock, unless you wish to include your NorthBridge and SouthBridge.

Assuming a computer is running at an average temperature, depends what average is nowadays. I have a Quad Phenom which runs at 40 - 50dc on Idle and 50 - 70dc whilst running rather CPU excessive programs, lets just say 30dc as an average temperature. A component running at 30degrees constantly with only a heatsink placed on the processing unit will start wearing away the multi-threads and memory interfaces, shown as the green chips below..

[black-dog]

I'd like to see references that your statement is true before you proceed to undermine on my comment.

OK.

http://www.smartcomputing.com/editor...714%2F0714.asp
"The biggest stress on any electrical system is turning it on. Bruce Drenning, network engineer for DPSC Technology Consultants, says turning on any electrical appliance produces an initial electrical spike that is generally three times higher than the amount of electricity needed to power the appliance."

http://www.associatedcontent.com/art...shut_down.html
"Thermal stress is the leading cause of system failure."

http://www.pctoday.com/Editorial/art...4w10.asp&guid=
"For years, many pundits have claimed that continually shutting down and restarting your computer more quickly wears out the power switch, drive motors, and other components."
..."It’s true that some PC parts expand as they warm and then contract as they cool; repeating this cycle several times throughout the day may very well cause more wear than leaving a computer on all the time."

http://www.pcguide.com/care/care/gen/powerOnOff-c.html
"Thermal Stress: After your PC has been off for many hours the components will be at room temperature. When the PC is turned on, the components will heat up, sometimes to much higher temperatures than 70 degrees F, causing them to expand. Then when you turn off the PC they cool down again, and contract. This cycle of heating and cooling causes thermal stress in the components that make up the PC, and is a leading cause of system failure"

http://lists.freebsd.org/pipermail/f...ry/075470.html

As far as cost of electricity is concerned I've done a few calculations. On average my machine probably uses around 100 watts. (http://windows.uwaterloo.ca/Hardware...onsumption.htm ) I work from home and like to have the computer available at all times, including evenings. So if I were to switch it off it would only be for a maximum of 8 hours. Electricity is about 10 pence per kilowatt hour and so I would save around £30 per year buy switching off. But then I would not be able to run my nightly virus check. However I always turn off my monitor.

[jon123]

In my opinion I think you are both right. I think most people will tell you that turning a light bulb on and off constanly not only draws more current, but actually decreases the life expectancy of the element because of the 'spiking' effect. That said, it is all relative to time isn't it!
If i were to switch on the light, then switch it off after 3 minutes then keep repeating it, it would cost me more in electricity and wear out the bulb more quickly.

I no nothing of thermal paste, but leaving a pc on for hours at a time when not in use is not only a waste of energy, but also needless wear and tear to the pc hardware. You will find that most mechanical, electronic equipment runs best when it has reached it's optimum temperature. A car for instance runs more efficiently the hotter it is, but you usually find the optimum temperature is reached very quickly anyway.
It takes literally seconds for the cpu to get hot doesn't it?
Also is it not true that all this atx stuff is all 'soft start' anyway? So the actual current drawn at switch on is fairly minimal? (of course we have not just the box but all the peripherals, monitor, etc) Am not sure but i know it obviously isn't like a mains switch for instance, where the really abrasive switching causes a huge current draw. I believe they call it 'back electromotive force', or they did when i was at college.

Saying all that, i am more concerned about leaving my monitor on, i'm quite worried about radiation tbh

[Dan]

The CPU will start getting hot after the BIOS screen and the Windows XP, Server 2008, Vista etc etc.. loading screen.

Agreed that switching things on constantly isn't the best, but neither is keeping them on all the time.

Maybe standby would be the best of solutions. Also switching computers on and off alot will also cause small damage to the PSU making the motherboard get spiked with small parts of Electronic Discharge.