so what? A computer is unused For a specified amount of time,
you can enable the following You can enable sleep.
Now, when you configure a device to sleep, here's what happens
goes into a low pile state.
The display is typically turned off on the hard disk spins down, but power is still being supplied to RAM.
If you were working on a document when your computer went to sleep,
but you had not yet saved the document
that the document is just there in RAM.
But it doesn't get saved when your computer goes to sleep.
Now the advantage of sleep is if you want to get back to your machine and start working on that document, all you have to do is move the mouse or press a key on the keyboard and it wakes up instantly and you can continue with your work.
But the danger with sleep is
supposing it goes in to sleep. You have a document that is in RAM but not yet safe to desk.
And then the power's lost. If it's a desktop computer, it could be that the mains power is lost.
If it is a laptop, it's battery. Could run out because remember,
when it goes to sleep, it's still consuming power.
It's consuming less power, but it's still consuming power. So eventually, if you leave it and sleep for long enough,
the battery could become exhausted and the system could shut off.
In either case, if it shuts off
anything that was in rhyme
but you had not yet safe to desk would be lost. Because, remember, RAM is volatile storage.
As soon as power goes from it, everything in Graham is lost
on alternative is hibernation. If you configure your system to hibernate when it's unused for a certain amount of time,
then the contents of ran a copy to desk
and once they've been safe to desk than the computer just shuts down.
So that point is not in a low power state. It's shut down. It's not consuming any power.
When you turn it back on,
the contents of Ram are copied back from the disk into rap.
So once it is working up from hibernation,
you can get on with whatever you were doing. And anything that was in grime that you had not yet saved has not been lost. It's still it's back in Graham again.
So Windows seven introduced a feature called Hybrid Sleep, and this is basically a combination of hibernation and sleep.
So when you configure this,
your system first copies the contents of rhyme to disk and then goes into a low power state.
The advantage of this is the following.
If you start using the machine again because it certainly got into a low power state, it doesn't have to boot up again.
And you could just continue working with whatever you were working on.
On the other hand, if it goes into hybrids, sleep
on dhe, then power is lost.
You don't lose your data because remember, before going into sleep mode, it saved the contents of RAM to desk.
So in that sense, it's a combination of the best features of hibernation and the best features. Off sleep
laptops can be configured to shut down, sleep or hibernate when the lid is closed.
So that might be something you want to configure. Had to indicate exactly what you want to happen. Remember the danger off certain some of these options if it is configured to say, go to sleep when you close the lead.
Here's what could happen. You could be working on a document. You have not yet saved it, and then you got called away.
So as you leave your desk, you close the lead.
The system goes to sleep,
but it's still consuming power,
and eventually the battery runs out. And whatever was in Graham at that point is then lost.
So in the power options, you can configure it to say, If I close the lid, shut it down or hibernated.
If the laptop is unused or batteries close to exhaustion, it can be configured to slow down the frequency of the CPU as well.
So when you're not very busy and there's not much CPU activity, it slows down the speed at which the CP runs and that conserves power.
Also, other devices that consume power, like the wireless network adapter, can be put into low power states
on dhe. They Obviously the display can be deemed or turned off.
Quite apart from all of that
on any type of device. With an LCD display, you can always reduce its power consumption manually by lowering the brightness of the display.
Now all these different settings
can be saved as a power profile
and Windows comes with a couple of power profiles pre configured with the number of thes settings already configured.
But you can also create your own power profile with your own particular combination of energy saving features that you want to enable.
Moving on from that and looking at how to provide power to computing devices.
Because we often have to plug in several devices, such as the desktop computer on its display monitor and maybe a printer, it is useful to have these power strips available.
Power strips can also be useful because they can often have search protection built in.
So if there is a sudden power spike in the mains
that is absorbed by the
and that prevents that surge from hitting the power supply of your computer and possibly damaging either the power supply or even the components on the motherboard,
Some power Strips can also indicate if there are wiring problems such as
they have miss configured the wires and say the live in the neutral wives are reversed or the ground wire isn't actually going to ground
on DSO there, maybe warning lights available on the power strip
to indicate when there are wiring problems within the premises
now, where, as a power strip can
at least save your devices from search protection.
Power strips cannot help you much if there's an actual power failure.
So to protect against that,
we can get a UPS uninterruptible power supply.
And this is important because if there is a sudden power failure, when you're in the middle off, say, writing a document that you have not yet safe to desk
the moment you got that power failure, your computer switches off and everything in RAM is lost.
But even if that isn't the case, even if you're not
having working on any document in RAM,
the computer could be in the middle of, say, writing something to the hard disk with the sudden power failure
and that would then corrupt whatever it was trying to write to the hard disk.
So to guard against both of those possibilities, you could get a UPS, plug that into the mains, and then you plug the computer and display into the ups
the ups typically contains. A battery on DDE
actually always contains a battery,
and that battery charges up while the power's being applied,
and if there's a power failure, it continues to power your computer on your display
for at least a few more minutes.
UPS is will also incorporate the other features. Such a surge protection,
on, they may show lots of other information. For example, this particular ups here is showing me what the current voltages that's coming in through the mains,
what the battery capacity is and what kind of a loaded currently has how much power is being consumed
by the devices connected to it
in terms of configuring a UPS. The idea is that if the power fails, the UPS should immediately notify the computer.
And this is typically done through a USB cable that comes from the ups when it's plugged into the computer. And then you configure the settings within the computer
now, typically, what a UPS does. It sends an initial notification when the power has failed,
and then you can configure it to send another notification when, say, the power remaining in the battery
it would send out one notification when the power fails. When they send out another notification when the battery is close, too exhausted.
And the idea is that when that second notification is received,
the operating system could be configured to say, hibernate the system and shut everything down before the batteries completely drained.
And that way, if you get a momentary power failure,
the initial notification goes to the PC.
But the PC takes no action, and then the power comes back, so there's no need to take any action.
In another instance, the power fails.
The computer gets the notification,
but then the power doesn't come back
so slowly. The battery in the ups starts to drain, and when it reaches a pre configured threshold, it sends a second signal to the PC. And at that point, the PC takes action by hibernating the computer
and shutting it down
on. Remember, hibernation saved the contents of RAM, so nothing in Graham is lost when you hibernate.
A few words on international power differences.
The mains voltage in the U. S. Is 100 and 20 volts.
But in many other countries, such as in Europe, it is 240 volts.
This does create issues. For example, if you are traveling with either a desktop or a laptop computer
before you plug it in Europe or in any country where the voltage is higher than 120 volts,
you need to be careful
in a desktop PC. If it supports multiple regions, then at the back of the power supply, there might be a switch you can flick to indicate to it that
you're now in an area where there are
240 volts coming out of the mains, not armed in 20 volts
with laptops. Check the adopters, see if it is universal
or states that it'll work with 120 or 240 volts.
Many adopters are auto switching
so that when you plug them in, they figure out what the voltage of the mainstays and adjust themselves accordingly. However,
do not take that for granted.
Some of these power supplies for laptops are for a single voltage. Only
on the problem is that if we go and plug
a device that's designed for 120 volts into remains of 240 volts,
it almost likely blow the device, and you also risk maybe starting a fire or something like that.
Next, we're gonna talk about device placement. I had the danger of electrostatic discharge.
When you're considering where to place computers and displays,
you should not install them in the following locations.
If there is inadequate airflow
so that the area around the computer gets hot and the heat can't be dissipated,
that's a problem. Because, as we now overheating can be a big problem with peces, causing erratic behavior, crashes, shutdowns and so on.
You should also not install computers and displays where there are high amounts of dust.
And these this dust could clog the fans and events within the PC again, leading to heat buildup,
it might not be a good idea, for example, to put a PC out in the midday sun
in a climate where the temperatures reach 90 degrees.
Because again, what happens? It's excessive heating
and overheating, an inability to dissipate
the heat. And then you get again crashes, sudden shutdowns and so on.
High humidity humidity is a big enemy of any kind of electronics.
On being constantly exposed to high humidity will damage electronic equipment.
It's areas where there are strong sources of electromagnetic interference, so earlier in the course, we've mentioned a few of these, such as
powerful electric motors, for example.
It wouldn't be a good idea to be close to the heating and air conditioning fans, which are usually fairly powerful. Motors that are in there.
But other sources of electromagnetic interference include microwave Auburn's fluorescent lighting on anything with an electric motor in it,
and do not install computers where they will be subject to shocks and vibrations.
Remember the mechanical hard drive within a computer?
You have this read write head that is floating a fraction of a millimeter above the platters
on. If there's a sudden shock, it can knock the head onto the platter. Physically damage it, and then you could lose any data that was in that location of the hard disk.
Electrostatic discharge. So many electronic components are very sensitive to electrostatic discharge.
Now, where does that
Our bodies accumulate the electrical charges as we walk around. For example, if you have rubber shoes on certain types of carpets as you walk, it creates electrostatic buildup within your body.
This becomes more of a problem in winter, when the air tends to be much drier
and you've probably experienced this that as you walk around in certain places,
you go touch the door handle
and you get a little zap of electricity
and us because your body has built up electrostatic charge. And when you touch that metal develop handle, it discharges through that.
The big danger is that if you touch electronic equipment while you're charged,
you could damage the equipment.