Just how "physical" is a physical shut down...
by djdrew103 - 6/16/12 1:36 AM
In Reply to: pc life by d_blitz13
When you shut down a computer you have to consider that you are actually only dealing with 3V, 5V, and 12V circuits as your 110v PSU transforms or reduces the power down to the converted voltage. So we aren't talking a huge surge of power when you turn one on.
In the normal lifespan of a computer, the amount of energy surge created from a cold boot or hard shut down compared to the energy impressed upon the system during normal usage for hours on hours in the Home User PC's life, well its simply trivial.
Your main worries are not the strain on circuitry components, but the strain on actual mechanical parts; power supply fans and case fans, hard drives spinning up and down, optical drives starting up during pOST (power on self/system test) and such. All of these are "mechanical components that will fail from the cold cool stress far more likely than the circuitry. What harms circuitry more than anything is the stress of temperature changes from a cold boot to a full running hot environment.
The CPU or processor runs the hottest naturally since it runs stable at common (between 42*C and 60*C).
If hard drives are mounted wisely and properly and have adequate air flow from case fans and routing of wires not impeding flow, then you have few worries to consider when concerned with drives.
The system bus is the most intricate and fragile of the circuits in a computer as compared to the far sturdier bus lines of graphics cards or pci card components slots , and little damage can be done to them even, unless you may have your computer in your barn to hide it from your Amish Parents and being in freezing temps, start with a very cold boot.
It is the general consensus though that a cold boot is harder on a computer and its components, than leaving a computer on at least through the day, and if you HAVE TOO, then shut it down just once daily, restarting it the next; ie: not turning it off and on frequently through the hours of a day.
So in the long run, your PSU or power supply will fail faster than anything most likely from cold boots since it is the only other hottest running item, plus mechanical due to a cooling fan spinning hour after continuous hour, yet at the same time you can purchase PSUs comparing their wattage AND their lifespan hours.
I leave my computer on ALL the time, even when sleeping simply because I feel the wear and tear savings doesn't justify over or above the cost of $5 or $6 added to my electric bill, to run one all the time. Though you are not worried about energy costs, its only and merely a slight difficulty to get an average dollar amount simply by adding up the wattage on components (a 95W or 125W processor, added to typical wattage for your video card(s) or motherboard Wattage if graphics are integrated, then figure per KiloWatt hour is all and at $.11 to .$.14 per KWH, you aren't going into the poor house for leaving your computer on 24/7.
You hours predicted for your spin life on a drive which isn't spinning unless your burning, or best example is the run time life of a power supply are the major components, and having to buy a power supply once every 6 years isn't a major price breaker of the deal.
Some have mentioned unplugging completely from the wall socket during thunderstorms, and although I think this is overkill, I won't take an opposing stand against the theology of the Demon Lighting Gods charging down to assail your computer on blackened wings in hordes and masses. Yet even in that scenario, a smart home pC owner would have a "surge protector" in between your power outlet and power supply cord rated at least at 4300 joules ($35 and up), and 6000 joules is far better but a bit pricier. Personally, I have twin Surge protectors piggy back'd for added protection just for the strength of that one millisecond of voltage in that area of surge that trips the switch internally, allowing two protectors to guard my ever precious system components. It has worked well for me over the last decade and I live in the tornado alley version of the Midwest with plenty of yearly storms.
So even though you might get allot of advice here, from those who seem admittedly stubborn about their opinions, you can see from this just some of the viewpoints to consider and yet alas then in the end, there's no set ground rules. You have to decide on your own what is best for you in your home environs, in your own personal scenario, and how you are affected by your own geographic locale.
Hope it helps even though its a bit confusing at times, you should be able to find a solution that will lessen the burden on your heart for good power planning and longevity for your system.