- Detailed analysis of form factors such as ATX, SFX and TFX to choose according to the case.
- Fundamental differences between modular, semi-modular and fixed cabling.
- Explanation of the 80 PLUS efficiency certifications and the advanced standard from Cybenetics.
- Internal workings of AC to DC conversion to protect hardware.
Sometimes we focus too much on the power of the graphics card or the gigahertz of the processor, but we forget that none of that would work without a reliable power supply . Essentially, it's the electrical heart of our computer; if it fails or is of poor quality, the other components can suffer serious damage or simply fail to start.
This device doesn't just pass current; it performs a complex process of electrical transformation and stabilization so that the hardware receives exactly what it needs. In this article, we'll break down everything you need to know about them, from size to efficiency ratings, so you don't get any surprises when building your computer.
How does a power supply actually work?
The process begins with voltage transformation . The electricity that comes from the household outlet is very powerful (usually 220V or 125V), so the power supply uses a coil transformer to reduce it to manageable levels, generally between 5 and 12 volts.
The problem is that the electrical grid supplies us with alternating current, which constantly changes direction. To prevent the PC from malfunctioning, a Graetz bridge rectifier is used , which converts this current into direct current, ensuring that the voltage always remains positive.
To prevent spikes or sudden drops, capacitors come into play . These components act as small reservoirs that store energy and release it gradually, resulting in a smooth signal without annoying oscillations.
The final step is regulation. A voltage stabilizer ensures that any external fluctuations do not reach the motherboard, thus guaranteeing a stable and safe power supply for all electronic circuits.
Varieties according to their form factor
Not all power supplies fit in all cases. Depending on the size of your PC case or tower , you'll have to choose between several standards:
- ATX: It is the most widespread and robust standard. It measures 150 mm wide by 86 mm high and is the preferred option for most standard towers.
- ATX12V: It's a direct evolution of the previous version. It has gone through several versions, from V1.0, which added the 4-pin connector for the processor, to V2.2, where the focus has been on... optimize energy efficiency.
- SFX (Small Form Factor): Ideal for those building Mini-ITX systems. They are much more compact (125 x 63.5 mm), although this means they have lower cooling capacity and power, usually below 500W. There is the SFX-L variant, which is slightly longer to accommodate a more powerful fan.
- TFX: With their elongated and narrow shape, they are the option for very compact equipment and offices, although their power is quite limited, normally They do not exceed 350W.
Cabling systems: Modularity and organization
Cable management is essential for proper airflow and to prevent your PC from overheating. Here are three different approaches:
Modular power supplies are the high end of the spectrum in terms of convenience. They allow you to connect only the cables you actually need, preventing the inside of your case from becoming a chaotic mess of excess cables, which drastically improves airflow.
On the other hand, we have semi-modular motherboards . In these, the essential cables (like those for the motherboard and CPU) are soldered, but the rest are independent connectors. It's a smart middle ground for those looking for a balance between cost and versatility.
Finally, there are non-modular or fixed-cable power supplies. All the cables come out in a single bundle. These are the most economical, but they require the user to hide the cables they aren't using , which can affect the internal temperature if not done carefully.
Cooling: Active or Passive?
Most power supplies use active cooling , meaning they have a fan that expels heat. The downside is that when the PC is under heavy load, the fan spins faster and can generate a considerably annoying noise.
There are also passive heatsinks, which have no moving parts and are therefore completely silent. However, these are only recommended in highly optimized configurations , because if the system consumes a lot of power, heat will accumulate quickly due to the lack of forced airflow.
Power and the world of certifications
The power range is enormous, from 180W to beasts of 2.000W. For the average user, it's typical to operate between 450W and 850W. But the most important thing isn't just how much power it delivers, but how much energy it wastes in the process.
The 80 PLUS certification is the most well-known scale. It tells us that the power supply is capable of maintaining at least 80% efficiency. The higher the category, the less electricity is lost as heat.
- White and Bronze: These are the basic options. The Bronze offers 82% efficiency at 100% load, a very slight improvement over the standard version.
- Silver and Gold: The Gold is the queen of value for money, achieving 90% efficiency at 50% load, which represents a real electricity savings and less noise.
- Platinum and Titanium: The top-of-the-range model. The Titanium reaches 90% efficiency even at full load, although its price usually soars above €150.
New standards: The arrival of Cybenetics
Since the 80 PLUS system has become somewhat outdated, Cybenetics was born , a much more rigorous standard that performs thousands of measurements to give an accurate verdict.
Its efficiency certification, called ETA Certification , is much more comprehensive, analyzing factors such as standby power consumption (vampire power) and power factor, forcing manufacturers to create more advanced internal designs.
In addition, Cybenetics measures noise using LAMBDA certification, employing anechoic chambers to determine the exact decibel level emitted by the fan. They also offer Delta certification , which assesses how well the case soundproofs against the noise generated by the power supply inside.
To choose the ideal power supply, it's essential to balance the required wattage with energy efficiency and the case size. Whether opting for the versatility of a modular unit or the precision of a Cybenetics-certified power supply, ensuring a clean and stable current is the best investment for extending the lifespan of all your hardware.
