WHAT HAPPENS IF THE POWER SUPPLY IS WEAK? 

WHAT HAPPENS IF THE POWER SUPPLY IS WEAK? 

In this article, we are discussing what happens if the power supply is weak

The power supply is a PC part that turns the 220 V from the network into the 3.3-12 V that different devices need. Many of them have nothing to do with the choice of a power supply, though.

They just take it in exchange for other parts they buy, usually at the same time as the case. But you shouldn’t do this if you’re building something more potent than a multimedia computer.

A bad power supply can easily damage expensive processors or video cards, so it’s best to buy a good one immediately.

Info Article: How to test a power supply with one of the best multimeters, but you can use the one you already have if you follow these steps (14 steps).

They just take it in exchange for other parts they buy, which is usually at the same time as the case. But you shouldn’t do this if you’re building something more powerful than a multimedia computer.

 Make sure you know how to test a power supply safely.

In order to use a multimeter to test the power supply when fixing a computer, you have to know how to do it safely.

Info Article: One of the most common components in a computer that creates problems is the power supply. As a result, you should be familiar with the signs and solutions to this type of PSU failure on your computer. Read our article on “How can you tell if a power supply is broken?” to find out whether your PSU is working properly or not.

Turn off everything

Most people might think this is obvious, but it’s important to remember that you should always turn off a computer’s power switch before trying to fix it. Unplug your computer while you’re at it to give yourself even more peace of mind.

Info Article: Not sure what power supply you need for your PC? Well, we are going to solve your doubt in this article, since we will give you the most important keys to knowing what features of a source depend on the equipment you have. In other words, we are going to teach you how to choose a source with the correct power, the necessary connectors, and appropriate to your needs. Read our article on “How do I know which power supply I need?

A bad power supply can easily damage expensive processors or video cards, so it’s best to buy a good one right away.

HOW NOT TO MAKE A COMMON MISTAKE WHEN CHOOSING A COMPUTER POWER SUPPLY.

  • . First, we have to find out how much voltage the power supply has. The lines for 3.3, 5, and 12 volts are as follows:
  • +3.3V: Used to power the system logic output stages (and generally power the motherboard and RAM).
  • +5V is used to power the logic of almost all PCI and IDE devices (including SATA devices).
  • +12V is the busiest line because both the CPU and the video card are powered by it.

Most of the time, 3.3 V comes from the same winding as 5 V, so they can see the full power. These lines aren’t used very often, so there’s not much point in paying attention to them if your computer doesn’t have 5 terabytes of hard drives and a couple of sound cards. It’s enough if the power supply gives them at least 100 watts.

But the 12V line is very busy because it has to power both the processor (50-150W) and the video card (up to 300W). This means that a power supply’s wattage is the most important thing about it (and this figure by the way is usually close to the total power of the power supply).

The second thing you need to watch out for is the connectors on the power supply. The video card doesn’t need two 8-pin connectors, but the power supply only has one. You don’t need to worry about this since every power supply has a main power supply with 24 pins.

Depending on the power of the processor and the motherboard, more CPU power comes in the form of 4, 8, or 2 sets of 8 pins. Make sure the power supply has a cable with the right number of pins (important: an 8-pin cable for a video card and an 8-pin cable for a processor are not interchangeable!)

Next comes the second power source for the video card. Some low-end solutions, like the GTX 1050 Ti or RX 460, get enough power from the PCI-E slot (75 W) and don’t need any extra power.

But the most powerful solutions may need anywhere from 6 to 2 x 8 pins; make sure your power supply has them (some power supply pins may look like 6+2 pins,

which is normal if you only need 6 pins). Then connect the main part with six pins; if you need eight, add two more pins on a separate cable).

The power for drives and other devices comes from a SATA or Molex connector. There are no split pins; just make sure that the power supply has as many connectors as peripherals.

If the power supply doesn’t have enough pins to power the video card, you can buy a 6-pin Molex adapter. On the other hand, this problem doesn’t happen very often with modern PSUs, and Molex is almost no longer on the market.

Power Supply Form Factors 

Power Supply Form Factors: 

These are chosen for the case, or if you choose a good power supply with a certain form factor, you’ve already chosen the case and motherboard.

Since ATX is the most common standard, you’ll probably see that. But there are also SFX, TFX, and CFX, which are smaller and better for people who want to build a very small system.

How efficient a power source is is measured by how much useful work it does compared to how much energy it uses. The 80 Plus certificate, which goes from Bronze to Platinum for power supplies, shows how efficient they are.

At 50 percent load, the efficiency is 85 percent for Bronze and 94 percent for Platinum. Some people think that an 80 Plus Bronze-certified 500W power supply can put out 500 * 0.85 = 425W.

This isn’t the case. The unit will be able to give out 500 watts, but it will need 588 watts from the network, or 500 watts times (1/0.85). In other words, if you have a better certificate, you will pay less for electricity, not more.

Since the price difference between Bronze and Platinum can be up to 50%, it doesn’t make much sense to pay more for Platinum, since it won’t save you much money on electricity for a long time. Besides that,

Changes in the way power works (PFC)

Modern blocks are getting more powerful, but the wires in the plugs don’t change. This makes impulse noise because neither the power supply nor the processor is a light bulb. Instead, they both use power in short bursts.

The load on the power grid is stronger and more uneven the more noise the unit sends into it. To deal with this problem, PFC was made.

This strong inductor goes after the rectifier and before the filter capacitors. First, it limits the amount of load current that the above filters can handle. When a device without PFC is connected to a network, it often makes a clicking sound.

This is because the current used in the first few milliseconds can be several times higher than that of the passport. This causes sparks in the switch. When a computer is running, the PFC module dampens the same impulses that come from different capacitors charging and hard drive motors spinning.

There are two kinds of modules: those that are passive and those that are active. The second one is different because the power supply’s low-voltage secondary cascade is connected to a control circuit.

This makes it easier to deal with interference quickly and get rid of it. Also, the PFC circuit has many strong capacitors, so if the power goes out for a fraction of a second, an active PFC can “keep” the computer from shutting down.

figuring out how much power needs to be provided

Now that we’ve finished talking about the ideas, let’s get to work. First, you need to figure out how much power each part of the PC will use. The best way to do this is with a special calculator. I think you should do this. You put in your processor, video card, RAM data, discs, number of coolers, how many hours a day you use your PC, etc., and then you get this graph (I chose the i7-7700K + GTX 1080 Ti option):

As you can see, when this system is working hard, it uses 480 watts. As I said, the load on the 3.3 V and 5 V lines is small—only 80 W—and even the most basic power supply can give that much. But the load for 12 V lines is already 400 watts.

You shouldn’t take two 500-watt power supplies right after each other. He will get by, but, first, if you want to upgrade your computer in the future, the power supply may become a bottleneck, and, second,

when they are running at full capacity, power supplies make a lot of noise. So, it’s best to keep at least 100–150 W in reserve and bring power supplies starting at 650 W. (they usually have 12 V lines with output from 550 W).

But there are a few things that are different here:

  • You shouldn’t put away and grab a built-in 650W power supply. All of them work without PFCs, which would protect them from power surges. In the best case, you should choose a new power supply. In the worst case, you should choose other parts (up to the processor and video card). Also, just because they say “650 W” on them doesn’t mean they can give that much power. Normal is a voltage difference of no more than 5 percent from the nominal value, and even better, no more than 3 percent. This means that if the source voltage is 12 V, the voltage difference should be no more than 3 percent. You can’t take the line because it has less than 11.6 V. On unnamed case-integrated PSUs, 100 percent load reductions can go as low as 10 percent, and even worse, they can cause the voltage to go up a lot, which can kill the motherboard.
  • On the box of the video card, it might say that you need a 400-600 W power supply, but it barely uses 100 W, and the calculator told me that it uses 200 W when it’s working hard. Do you really need a power supply with 600 W? Absolutely not, not at all. Companies that make video cards are heavily reassured and purposely overestimate the power supply needs, so even people with a power supply built into the case should be able to play (because even the 600 Simpler W shouldn’t sink under a 200W load).
  • Get a PSU that is 1.5 times or even 2 times more powerful than what your system needs if you want a quiet build. At 50% load, a PSU might not even turn on the system’s cooler to keep it cool.

As you can see, choosing a power supply isn’t too hard. If you choose one based on the points above, you’ll make sure your PC works well and doesn’t break down because of a bad power supply.

When the systems’ energy use was measured, it was pretty close to what was expected. If a computer didn’t have a separate graphics card, it probably could run on any compatible power supply. Things that are very old can also be seen.

The AMD Phenom II X4 965 processor uses a lot more power than a less powerful Intel i7-3770K core model. Technically, though, all four systems could work well with a 450W power supply (corresponding quality with honest watts).

So who needs 1000W power supplies? Obviously, they can also be used for real things, like if you have a game system with three video cards that cost about 100,000 rubles all together.

Some storage fans can’t help but put in 20 hard drives and a bunch of extra controllers, but a 550W power supply is enough for most normal and even powerful systems. Office PCs without discrete video or with low-end devices will be able to use one of the power-saving devices for sure.

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