When it comes to building a PC, it always starts with what you see on the screen. You want those realistic-looking graphics delivered to your monitor without lag, and you start your research process accordingly.
And it makes sense, but it takes little time to realize the performance of your final build depends upon the performance of individual components.
And if you are not particularly tech-savvy, you may not fancy benchmarks, comparisons, or parameters, but unfortunately, there is no way around that.
You don’t need to be a hardware expert to build a good PC, but you must know a few essential metrics to get the proper performance out of your PC.
I will not bore you with describing all those parameters in a single article. That would be counterproductive.
Instead, I will create articles explaining these parameters and how they impact performance.
I feel that would be a better approach. Today let us discuss TDP or Thermal Design Power.
So, does lower TDP mean less heat?
TDP indicates power consumption but not directly. So, a CPU with more TDP will consume more power, thus generating more heat and delivering proportional performance. A CPU with a lower TDP will consume and emit less heat, but more factors must be considered before commenting on performance.
In the subsequent sections, let us understand what TDP is a little more deeply and how you can apply that understanding to build a better PC.
And as you will see, understanding TDP goes beyond just building a good PC.
With a good understanding of what TDP is and what it signifies, you will know what cooling mechanism to use and save on your electricity bill while at it.
What is TDP?
So, what exactly is Thermal Design Power or TDP?
Sometimes referred to as Thermal Design Profile, TDP is a parameter that ‘indicates’ the maximum power a CPU generates when under load.
Indicates is the important term here. Almost all manufacturers use the term TDP to advertise their products.
But TDP does not directly equate to power consumption or generation.
Many people make the mistake of considering TDP equal to net power consumption, which isn’t technically correct.
The reason why this happens is that TDP is expressed in Watts, and so is electrical power. When TDP is expressed in Watts, the manufacturers refer to thermal Watts, not electrical Watts.
The thermal Watts, when used for TDP, signify that you need a cooling mechanism capable of dissipating that amount of heat.
So, a CPU with a rated TDP of 65 watts will need a cooling mechanism capable of dissipating 65 Watts of heat.
It’s also true that if you want to dissipate the heat represented by TDP, it must also be generated.
Therefore, TDP is also sometimes used to indicate the heat a chip generates loosely.
So, the next time you see a manufacturer quoting TDP, you need to think of a cooling mechanism to remove that amount of heat.
What is also worth pointing out here is that most TDP values are generated when the chip is running a typical workload.
You cannot take TDP face value at full workloads.
When you are running full-throttle benchmarks or a demanding game/application, your cooling mechanism should be able to take away heat much above the rated TDP.
Interpreting TDP to Performance
Now that we understand TDP, what inferences can we make from its value?
Is having a high TDP desirable, or should you get a CPU with a low TDP?
As discussed, a CPU with a high TDP will generate a lot of heat. Talking strictly in terms of electricity, this may seem like it’s a bad thing.
A high TDP also means the processor will require a more expensive cooling mechanism.
Both of these factors combine to give the impression that having a high TDP is a bad thing.
However, the capacity to draw more power from the source also means the CPU is faster and offers superior performance than a CPU with low TDP.
So, when you are shopping for a CPU, and your intention is high performance, you will generally have to settle for a CPU with high TDP.
Will having a high TDP CPU mean getting an expensive cooler too?
Not necessarily, but I recommend doing the due research. As I said, you cannot take TDP vales at face. The TDP values are generated based on typical workloads.
But if you intend to overclock the CPU, you need a good cooler that can take away the heat, which will practically be much higher than the rated TDP.
Here is an example of how much the TDP values can differ on paper and in real-time applications.
Newer CPUs like Ryzen 5 5600X come with stock coolers that do a very good job at managing CPU temperatures.
But if you want to push the performance limits to the extreme, more often than not, you would want a better cooling system.
On the other hand, if you are aiming for a stable power-efficient performance (servers), it may be wise to go with CPUs with lower TDP.
As technology progresses, we are seeing more and more processors that offer high performance at low TDPs.
This happens because, with better technology, transistor size gets reduced, and more of these transistors can be fabricated in the same space, generating less heat.
TDP and Cooling Mechanism
Two cooling mechanisms are used to take away the heat of chips in a PC; air and water cooling.
Cooler manufacturers use a chip’s TDP value to develop cooling systems that help maintain the chip’s specified performance level.
A cooling system(air or water) rated at 95W can effectively be used with a CPU rated at 95W TDP. That being said, it is always recommended to use a cooler that is rated at a value higher than that of the CPU’s TDP.
This is because of a variety of reasons.
Prominent among them are,
- Clock Speeds
As I mentioned in a previous section of this article, you should not take TDP value at face for all situations.
One of the situations where the rated TDP value falls on its face is in overclocking.
The TDP values for an overclocked CPU are far higher than what you will see on the specifications chart. Most specification values are created on typical workloads, not extreme workloads.
Therefore, if you are preparing a system that you wish to overclock, you need better cooling mechanisms to dissipate the generated excess heat.
Stock coolers, in most cases, will not work.
- Chip Deployment
Not all CPUs will be subjected to the same environment. For instance, laptops, notebooks, and similar mobile CPUs have low TDPs.
The low TDPs CPUs on laptops help keep the battery life better.
Regarding desktop processors, TDP doesn’t need to be low, as desktops are designed for performance.
Today manufacturers are also creating CPUs of which TDPs can be modulated using configurable TDP mechanisms.
- CPU form factor
The size of a CPU influences its TDP too. Large CPUs require more power to operate and thus release more energy.
For example, if you compare two CPUs from Intel viz. Intel Celeron N4000, and the Core i7-8850H, the N4000 (25 mm x 24 mm) has a TDP of 6W. Contrast that with 8850H (42 mm x 28 mm) has a TDP of 45W.
The point is TDP is not an absolute value. Yes, it indicates the power generated by the CPU during typical workloads. Still, it can significantly change due to overclocking, intense games/applications, CPU form factor, use cases, etc.
I hope I was able to create a sound knowledge base on what TDP is and how to think about it in relation to PC performance.
When you build a PC as a beginner, your performance measure is often done using factors like how many fps you want or what applications you wish to run.
And there is nothing wrong with that. When I built my first PC, as far as TDP was concerned, all I researched was, will the Ryzen 5 1600 work well with the stock cooler?
Thankfully, it did work well till I started thinking about overclocking it.
When you start thinking along the lines of ‘extracting the best performance out of a PC,’ understanding parameters like TDP becomes super important.
And I hope I have done a good job of explaining it.
Here are a few more frequently asked questions that should help you further understand TDP.
Is TDP Only for CPUs?
More often than not, TDPs are discussed in conjunction with CPUs. But TDP is also a specification used to study the performance of processors, graphic cards, chipsets, and SoCs for smartphones.
Is a higher TDP CPU better for gaming?
A higher TDP indicates that the CPU can handle more power than a CPU with a lower TDP. More often than not, this translates to better CPU performance, but other factors must be considered to make a conclusive statement about gaming performance.
Do motherboards have TDP?
TDP values are not exclusive to CPUs. Any system that uses electronic chips can use TDP values to relay its heat generation. Motherboards sometimes give a TDP value dictating the maximum TDP value CPU it can support, or sometime motherboard manufacturers use a smaller TDP value to relay its chipsets’ power consumption.
I hope you enjoyed the article as much as I enjoyed writing it.
If you have any other questions regarding TDP and its significance, let me know in the comments section below.
In the upcoming articles, I will pick similar hardware parameters and relay their significance so that you can build a PC that better serves your purpose.
So, subscribe to the blog, so I can notify you when the articles are out.
Take care of yourselves, and I will see you at the next one!