Choosing a CPU (Computer Processor) 

Whether you’re looking for a regular desktop PC or an industrial computer, one of the first things that you should consider is the processor that’s going into your PC. Oftentimes, people want the most powerful processor for their computer without thinking about whether they will actually need or use that processing power. That said, before asking for the most powerful processor, one should consider the cost of the more powerful processor and the energy needed to power that processor. Energy costs become extremely important when you are deploying hundreds or thousands of systems, so it should be something that you consider before purchasing a computer. If you are a gamer and want to purchase a powerful processor, sure, go ahead because chances are you will benefit from the performance; however, if you are looking to configure an embedded computing solution that’s going into a mission-critical deployments with environmental challenges, you should focus on the TDP of the CPU. TDP is denoted in terms of watts – 7W, 15W, 25W, 35W, 65W, 95W, etc. TDP, or Thermal Design Power, is a crucial specification for Central Processing Units (CPUs) and other semiconductor devices. TDP represents the maximum amount of heat that a CPU is expected to generate under a heavy and sustained workload. It is measured in watts (W) and serves several important purposes: Heat management, Power Supply and Motherboard Selection, System Reliability, Performance vs. Efficiency, and Cooling Solutions.  

• Heat Management: TDP is a critical factor for designing the cooling system in a computer. It helps determine the size and type of heat sinks, fans, or liquid cooling solutions required to keep the CPU's temperature within safe limits. 
• Power Supply and Motherboard Selection: The TDP rating is essential for selecting an appropriate power supply unit (PSU) and motherboard. A CPU with a higher TDP will typically require a more powerful PSU and a motherboard with a robust power delivery system that can support the overall power consumption of the system. 
• System Reliability: Excessive heat can degrade the performance and lifespan of a CPU. TDP provides a guideline for system builders to ensure that a CPU operates within its thermal limits, thus contributing to system reliability. 
• Performance vs. Efficiency: TDP is used by consumers to understand the balance between a CPU's performance and power consumption. Lower TDP CPUs tend to be more power-efficient but may sacrifice some performance, while higher TDP CPUs offer more performance but may consume more power and generate more heat. 
• Cooling Solutions: Manufacturers of cooling solutions, such as heat sinks and fans, use TDP ratings to design and market products suitable for various CPUs. 

It's important to note that TDP is not a direct measure of a CPU's power consumption but rather its heat generation. The actual power draw of a CPU can vary based on its workload, clock speed, and power management features. Therefore, TDP serves as a useful base guideline, but it does not provide a precise estimate of a CPU's energy efficiency or power consumption under all conditions. 

Processor Power vs. Power Consumption 

When choosing a CPU for your desktop computer or industrial computing solution, you should be aware of the processor power and processor power consumption. Although they sound very similar to each other, these are two very different terms with different meanings. Processor power is usually provided in GHz. For example, you will find a processor as having, for example, 3.5GHz, 4.0GHz, etc. On the other hand, the power consumption of a CPU is defined in terms of TDP (thermal design power), which provides you with the maximum heat a computer chip such as a CPU can use in watts. It also provides you with the power consumption of a PC.  

Typically, the higher the TDP, the better the performance of the processor. In many gaming PCs and high-end PCs, you will find CPUs that yield a high TDP. However, embedded computing solutions, such as those provided by Premio, are usually configured with low-TDP CPUs (35W) because they are passively cooled without fans and are designed for environmental challenges like wide operating temperatures. As a key design principle, passively cooling a PC only works with lower-TDP processors due to the need for robust thermal dissipation from heat producing electronics. More powerful and higher TDP processors often require active air cooling from physical fans for thermal air circulation that regulates heat as passive heatsinks are not enough to dissipate all of heat. The higher the TDP of your processor, the more power it will consume, meaning you will end up paying more in energy costs to run your PC. 

The Ideal Processor for Industrial and Embedded Computers 

Suppose you are deploying a PC for an industrial application, such as powering a kiosk machine or an IoT gateway in an industrial setting. In many of these cases, you probably don’t need the most powerful processor that is currently being sold on the market. Instead, you need a processor that’s reliable and can efficiently perform repeated tasks without fail. If you buy a processor that’s too expensive, you’re throwing money away because you would never be able to use it to its full potential. On the opposite end, you should also not choose a processor that has less power than what you need.  

Skimping out on a processor is much worse than buying an over-powered processor, as you want your system to function reliably and smoothly without failures. Configuring a system with less power than what your applications require will result in your system operating poorly and sluggishly, crashing, or thermal throttling; all factors that can easily disrupt the normal flow of your business.  

Low-Power Processors for Industrial and Embedded Computers 

In the world of low-power embedded computing solutions, such as fanless industrial computers, ideal processors should strike a balance between performance, power efficiency, and compatibility with the specific requirements of the embedded system. Leading semiconductor companies like Intel or AMD will design and offer a wide portfolio of processors for both high-performance and low-power embedded computing. The variety of these processors allows original equipment manufacturers like Premio to evaluate the best performance for specific applications and deployments.  

When Premio’s computing engineers go through the process of selecting a processor for the next embedded computing solutions, several key factors are considered to ensure the right CPU offers the most mission-critical reliability and performance for any specific industrial application. These factors include: 

Architectural Choice

Depending on the application, a choice between ARM-based, x86-based, or other architectures. ARM processors are commonly used in low-power embedded applications due to their energy-efficient design while x86 processors provide low TDP processors for new use cases in IIoT and Edge AI.  

Power Efficiency

Processors with low Thermal Design Power (TDP) or power consumption. Processors based on ARM architectures, such as those from the Cortex-A and Cortex-M families, are often known for their power efficiency. As for processors on the x86 architecture, Intel (ATOM) and AMD (Embedded R & V Series) have their own lines of embedded low-TDP processors that deliver incredible performance and power efficiency.   

Performance Requirements

Evaluate the performance needs of your application. Low-power processors typically offer less computational power than their high-performance counterparts. Ensure that the selected processor can meet the specific performance requirements of your application. 

Peripheral Integration

Processors with integrated peripherals, such as GPIO (General Purpose Input/Output), USB, I2C, and SPI interfaces are all considered to reduce the need for additional add-on components and minimize power consumption. 

Operating System Compatibility

Our engineers carefully select a processor that is compatible with the operating system or real-time operating system (RTOS) required for common industrial applications. For example, Microsoft Windows IoT has a Long-term service channel (LTSC) version that is designed for IoT devices and computing solutions. Each specific CPU needs to be compatible with the Windows IoT version for entry, value, or high-end.  

Longevity and Availability

Embedded systems often have long lifecycles. Processors from manufacturers that offer long-term availability and support to ensure continuity of supply and updates. For example, both Intel and AMD offer embedded long-life support for specific models up to 10-15 years.  

Customization

Some processors allow for customization of the core, clock speeds, and power profiles. This can be valuable in tailoring the processor to your specific needs. 

Security Features

Depending on your application, you may need processors with built-in security features, such as hardware encryption or secure boot capabilities to protect sensitive data from being lost or stolen.  

Form Factor and Packaging

Some embedded processors are designed for compact and ruggedized environments, which can be advantageous for certain applications where space is limited. For example, socket type CPUs require additional cooling while BGA type solder down CPUs use less power and require minimal cooling.   

Ecosystem and Development Tools

Ensure that there is a robust ecosystem of development tools, compilers, and libraries available for the chosen processor to facilitate software development. 

Cost

Consider the cost of the processor and its impact on the overall system budget. Balance performance and features with cost constraints. 

Environmental Considerations

Takes into account the operating environment. If your embedded system is deployed in extreme conditions, look for processors that can operate within specified temperature ranges. Ruggedized and hardened computing solutions provide reliable heat resistant computers and vibration resistant computers for challenging environmental conditions. 

How Much Money Will a Low Power Consumption CPU Save You Over a High-Power CPU? 

The first factor that you should you consider when choosing a high TDP processor over a lower TDP processor is the cost of the processor itself. Lower TDP processors are often half of the cost of the higher-end models, which means you’ll save a significant amount of money by simply purchasing a low-TDP processor. 

Second, you should consider the cost of energy needed to power your processor. The formula for calculating the power consumption of your processor is as follows:  

To calculate the cost of power consumption, we are basing the following calculations on the average price of $13.20 per kilowatt. Using this average value, we can calculate:  

• 7W TDP – (7/1000) X .13 X 24 X 365 = $8 per year 
• 15W TDP – (15/1000) X .13 X 24 X 365 = $17 per year 
• 25W TDP – (25/1000) X .13 X 24 X 365 = $29 per year 
• 35W TDP – (35/1000) X .13 X 24 X 365 = $40 per year 
• 65W TDP – (65/1000) X .13 X 24 X 365 = $74 per year 
• 95W TDP – (95/1000) X .13 X 24 X 365 = $108 per year 
• 125W TDP – (125/1000) X .13 X 24 X 365 = $142 per year 

These numbers are meant to illustrate how big of a difference the TDP of your processor can make in your total energy costs. It’s common to find gaming PCs that are equipped with i7 and i9 processors that can consume anywhere from $75 of energy to $142 per year. That said, when it comes to industrial computing solutions, you will find that many processors consume anywhere from 7W to 35W, with some CPUs consuming as much as 65 Watts of power.  

It’s important to note that these calculations are based on a system that is in operation 24 hours a day, 7 days per week, which is not uncommon for industrial computers that are deployed to handle industrial workloads that require the system to remain powered on all day long, every day.  

If you’re deploying many industrial computing solutions, the math will reveal even more. For example, if you’re deploying 100 industrial computers, each with a TDP of 15W, you are looking at a total yearly electricity bill of $1,700 for all your systems. However, if you deploy a more powerful 65W TDP CPU, you are looking at a yearly electricity bill of $7,400. This makes the lower-powered industrial computing solution more than $5,700 cheaper annually than the higher-powered system.  

Heat and Computer Processors 

Typically, the more powerful your processors, the higher the TDP; and the higher the TDP, the more heat that will be produced by your CPU. For example, if you purchase a 95W TDP processor for your gaming rig, you can expect your CPU to produce a lot of heat. To cool down your gaming PC, you can use a powerful air-cooled or liquid cooler to move the heat away from your CPU to keep it performing optimally. That said, for industrial computing solutions, the equation is different. Many industrial PCs are fanless, meaning they passively cooled via heatsinks. They are passively cooled to create a totally closed system that can be deployed in challenging environments. Anything with a higher TDP would require active air cooling via the use of fans because it would simply produce too much heat to be cooled down with a heatsink. Fans and liquid cooling are not suitable for non-traditional and harsh industrial environments, where factors such as dust and debris can drastically ruin an entire system if entered through any ventilation. Therefore, embedded CPUs are used for embedded computing solutions because they have a lower TDP than consumer-grade parts. For example, some fanless industrial computers feature 35W TDP CPUs and even 65W TDP CPUs that are passively cooled via heatsinks.  

Using a cooling solution that can move the heat away from the CPU efficiently is a must, regardless of what type of computer you have at hand. If a CPU gets too hot, it will thermally throttle, meaning it will reduce its performance to ensure that it does not damage itself. That said, thermal throttling severely impacts the performance of the system. If thermal throttling does not work to cool down the CPU, the CPU may shut down the entire system, causing detrimental downtime for many businesses and users. So, it is important to consider the cooling solution and CPU TDP when selecting a CPU for your system. Overlooking this could result in poor performance or, even worse, system damage.  

Bottom Line 

When choosing a CPU for your PC, you should choose a processor that has sufficient power to run your applications. Choosing a CPU that does not have enough power or choosing a CPU that has too much power can cost you money in the long run. So, selecting the right processor will help you eliminate wasteful power consumption and will save you money on the CPU itself. That said, you should always consider the TDP of the processor and select an appropriate cooling solution to ensure that the system does not thermal throttle or damage itself. If you need assistance choosing an industrial computing solution, please contact us, and one of our embedded computing professionals will assist you with choosing a system that meets your specific requirements.  

If you need assistance configuring your system with the appropriate CPU, please contact us, and one of our computing professionals will assist you with putting together a system that meets your specific requirements.