→ Undervolting: what is it? what is it for? and how to do it ??

Surely you will have heard about overclocking, but about undervolting you will have heard or read little or nothing. In this quick tutorial we explain what it is, what it is for, its benefits and how we can do it quickly. Is it really worth it?

The current silicon architectures make them require less energy to function, they also take better advantage of it, but there are basic physics rules such that the higher the energy consumption, the more energy transformed into heat.

The less heat, the better an electronic component works (up to certain limits at very low temperatures) so when we reduce the consumption of any of our components it will improve its temperature and consequently we will also make it more stable. Even so, not everything is so simple so we are going to tell you that it is Undervolting, because some users perform this technique and we will see the basic steps of how to do it on your CPU or GPU.

Index of contents

What is undervolting?

Undervolting is nothing more than reducing the standard electronic chip working voltage. This means that if our processor has a working voltage of 1.2v to develop its full potential, we can force it to reduce that consumption, in short, to improve its thermal behavior.

The objective of this technique is to carry out this process without losing the full potential of the processor, although sometimes it can be combined with other techniques such as underclock, to further improve the main objective of Undervolting.

As you can see the concept is simple, now we will see exactly what we can get out of it and when it is most useful this type of technique is that it is very easy to execute and that it can be useful to us on many occasions.

What is it for?

Undervolting reduces the consumption of the processor, GPU or other encapsulated components. By reducing consumption we will improve energy efficiency, that is, we will consume less and less energy will transform into heat so we will need less cooling to keep our component working. Less cooling also means less noise and also that we can mount that component in environments where cooling, by size, is a bigger problem.

Undervolting is done a lot in cryptocurrency mining with GPU since in sustained stress for a long time each watt of consumption is important, since we will earn more money, but it is also important because we will reduce the thermal stress of the component and therefore it will last longer.. As you can see, Undervolting is essential for a cryptocurrency miner, but it can also be for any user.

Every electronic component or better said every silicon processor, no matter how complex it is, has some degrees of quality in its production, for example, the processors of the wafer edges are usually of lesser quality due to the lithography process itself. This means that the manufacturer always gives an interesting range of voltages that is supported by your silicon so that it works well whether it is of high quality or not.

With this power margin, the user plays with to perform Undervolting without losing performance or without losing stability and in some cases, especially on GPUs, it also improves overclocking capacity. As you will understand we will also have, as in the case of other techniques, better or worse results depending on the quality of our chip. So there is some randomness in the result as it happens when we overclock, which is a more widespread technique.

How can I undervolt my CPU?

Current processors have different voltages that can be used in this technique, but the most effective is still touching the vcore or the main voltage of the processor. Currently these voltages are variable to adjust the processor to the rest states of the system, so we have to do the Undervolting in an intelligent way.

If we force a low voltage we can have stability at rest, but not under load and lose, for example, the turbo frequency capacity of the processor, if we use a high voltage, but reduced at the maximum peak of the processor, we will have less load consumption, but we will have more consumption in idle states so what we gain on the one hand we will be losing on the other.

My advice, therefore, is to use a voltage reduction based on a relative vcore decrease. Almost all modern motherboards allow it and it is nothing more than reducing a few tenths, those that we consider appropriate for our objectives, to the variable vcore of the processor. In this way, if our processor goes up to 1.2v when loaded, we will force it to use 1v, and if it uses 0.6v at rest, then ours will be 0.4v.

Each motherboard manufacturer is different but almost all have these options, we will have more difficulties if our motherboard does not have those characteristics, but then we will always have the option of using the Intel XTU application, if our processor is compatible, or the Ryzen AMD Master for AMD Zen Processors.

How to do it on my graphics card or GPU?

The process is more or less similar since modern graphics uses processes similar to those enjoyed by modern CPUs. That is, they both use variable voltage systems that adapt to the consumption needs of the GPU based on the needs of the user. In this way, modern graphics processors are able to substantially reduce consumption when not all of their power is required.

Depending on the graph, the adjustment in one way or another, we may only affect its maximum consumption mode, so when we modify this variable we are only affecting the most demanding states of the card, or that we can detail, as is the case of many recent AMD graphics, multiple voltage levels according to the states that the card supports. The settings, as in the case of a CPU, are light, of tenths or hundredths of a volt, but the results are important.

We can use applications like MSI Afterburner or others directly from the manufacturer, such as the AMD Wattman, to control this aspect and others. Not in all the graphics it will be possible to perform Undervolting, it will depend a lot on the options that the manufacturer wants to give us to manipulate these aspects of our hardware. Another option is to modify the bios of our graphics card and flash the bios of it with the updated parameters. It is something feasible and easy to execute, but it will invalidate the guarantee of our card so it is something to consider if it is worth it.

Real differences in consumption and temperature using Undervolting

We have made some very interesting real tests of how this technique can affect the consumption and working temperature of important components such as a CPU and a GPU. In our tests we have used standard frequencies for both components, without overclocking, to get an initial idea of ​​the results. This technique, of course, can be combined with others, such as overclocking, or also underclocking, to achieve different results.

Testing on an Intel Core i5-9400F processor

Tests on an AMD Radeon RX 590

Final words and conclusion about undervolting

As you can see, this technique can have important results in the consumption of the components where we apply it. We can reduce consumption and therefore also the temperature and therefore allow ourselves less noise in the ventilation of the component or that we can mount it in environments where we have less cooling capacity.

Surely you are interested in taking a look at our guides on hardware:

• Best processors on the market Best motherboards on the market Best RAM memory on the market Best graphics cards on the market Best SSDs on the market Better chassis or PC cases Better power supplies Better heatsinks and liquid coolers

What do you think of all this about undervolting ? Will you apply it to your processor and your graphics card? We want to know your opinion.