as well as restarting the computer shortens the life of the cpu and the other components because of the initial electrical current? In this context it was said that it's recommended to keep the computer either on or in sleep mode and restart it only once a week to clean memory. Has anyone else heard that theory? I'd like to hear also from hardware experts.

I have heard of this theory but have always turned mine on and off. One reason I am not happy to leave mine on is in case cooling fan fails as they sometimes do. Now, I know in theory a thermal cut out should cut in but a lot of the Power Supply Units people have in their computers is very cheap quality made in China and I am not prepared to assume that it will cut out as opposed to causing a fire from overheating.

It may shorten the life of the hardware, but only by a tiny, tiny bit. Chances are, you'll probably want a new computer way before your current one "burns out". I turn all of my puters off at the end of the day. Keeps the temperature down and saves a couple electrical bucks. Every little bit counts. :P My Super P3: Pentium III-S 1.4GHz @ 1.5GHz, 512K L2 X800XT All-in-wonder, overclocked to 580/600. 250GB HD 2 gigs of PC2100 RAM QDI Advance 12 mobo, this baby rocks! SB Audigy 2

well, i dont know about that, but i have an old PII Dell, it has restarted for a million times, and its still work fine today. its more than 8 years old now. the PC i am using today is 3 years old and it has restarted for countless times as well. some programs require you to restart the PC. dont worry about it.

Someone who answers on the site frequently started his answer to this FAQ with - "A computer is not a light bulb!" and I think that is very apt. I have always turned off the power to my computers overnight and when on vacation. I start up my computers several times a day, nearly every day, and when I know I'm not going to be using them for several hours I also shut off the power to them during the day. I have been doing these things constantly with increasing frequency since about about 1989. I have not had any problems out of the ordinary because of that. Restarting the computer when it's already operating won't hurt anything at all. Starting up the computer from cold (off and cool)or warm will not hurt the cpu. It's voltage is tightly regulated by components on the mboard. It may draw a bit more current when first started up than it does when "idling", but doing things that demand a lot more of your cpu such as burning a CD or DVD, or playing a demanding game will draw a lot more current, and the cpu is designed to handle any of that. Hard drives do draw more current spinning up than they do otherwise, but hard drives draw very little power in any case. The effects of thermal cycling on adequately cooled computers are minimal from what I've seen. Early computers had a problem with ram "chip creep" because of thermal cycling, but that hasn't been a problem with ram in more modern ram slots, since the early 80's . The PS produces related accurate voltages, and there is insignificant if any change in the voltages it produces whatever you do with your computer. On the other hand, having your computer on 24/7 in one form or another when you don't need to just because you're afraid it won't last as long if you are constantly turned it off and on is not wise. ATX power supplies are always powering ATX mboards, even when Windows is Shut Down or in Standby or Hibernate modes. Good quality PSs are less likely to fail than el-cheapo PSs, but any power supply can fail at any time, even when the computer is in Standby or Hibernate modes - that may or may not damage your mboard or other components. PS fans tend to last a long time but they have a finite life and often they are the first thing in a PS to fail. If the PS fan spins too slowly, or stops spinning, most PSs will fry in a short time, or if it takes a while components inside the case will probably eventually be damaged by the excess heat. If any of that is going to happen anyway after x hours, it will happen sooner relative to the time useful to you if the computer is on 24/7. At the very least, you will get less useful life out of your hard drives if they are spinning 24/7 - if they are going to fail, they will fail sooner, relative to the time you are actually are using them. Which is more likely to shorten the useful life of your hard drive - frequently starting or restarting it, or leaving it on 24/7 spinning all the time? - I would say the latter. (You can minimize that by setting your power settings in Windows to turn off the hard drive after xx (time) inactivity - it will stop spinning, but starts up again when you move your mouse or press a key, etc.) CPU and case fans have a finite life - if your system isn't set to shut down the computer when temps of the cpu or inside your case get too high, your cpu will fry, or components inside the case will probably eventually be damaged by the excess heat if the case fans actually helped cool the case that would be too hot otherwise. They are going to fail sooner, relative to the time you are actually are using the computer. And the inside of your case will get dirty faster, relative to the time you are actually are using the computer.

...computers is very cheap quality made in China... It may be true but remember that everything they manufacture has to meet the customer engineering standards. Go HERE and then scroll down to page 2. You will see a chart that show the typical system component allowable number of power cycles in lifetime. i_XpUser

A little hdd lesson when you perform a gracful shutdown the hdd heads have a chance to park in the track zero position resulting in the hdd not being started up with the heads on the platen which can be easily dammaged which will cause the bad clusters and more hard errors on the hdd in time can cause the hdd to crash