NETINT Blog

Is power consumption your company’s priority?

Jan Ozer and Matthew Ariho - NETINT Technologies
January 9, 2023

Power consumption is a priority for NETINT customers and a passion for NETINT engineers and technicians. Matthew Ariho, a system engineer in SoC Engineering at NETINT, recently answered some questions about:

How to test power consumption
Which computer components draw the most power
Why using older computers is bad for your power bills, and
The best way for video-centric data centers to reduce power consumption.

What are the different ways to test power consumption (and cost)?

The Kill A Watt multimeter

On the hardware side of things, you can use different forms of multimeters, like the Kill-A-Watt meter and a 208VAC power bar are examples of such devices available in our lab.

What are their pros and cons (and accuracy)?

Matthew Ariho

The IPMItool is great because it provides a lot of information. It is fairly simple to set up and use. There is a question of reliability because it is software based, it depends on readings whose source I’m not familiar with.

The multimeters (like the Kill-A-Watt meter), while also simple to use, do not have any logging capabilities which makes measurements like average or steady state power draw difficult to measure. Both methods have a resolution of 1W which is not ideal but more than sufficient for our use cases.

What activities to you run when you test power consumption?

What’s the range of power consumption you’ve seen?

What’s the difference between Power Supply rating and actual power consumption (and are they related)?

Matthew Ariho

Power supplies take in 120VAC or 208VAC and convert to various DC voltages (12V, 5V, 3.3V) to power different devices in a computer. This conversion process inherently has several inefficiencies. The extent of these inefficiencies depends on the make of the power supply and the quality of components used.

Power supplies are offered with an efficiency rating that certify how efficiently a power supply will function at different loads. Power consumption measured at the wall will always be less than power supplied within a computer.

What are the hidden sources of excessive power that most people don’t know about?

What distinguishes a power-hungry computer from an efficient one – what should the reader look for?

Matthew Ariho

The power supply rating is something to watch. Small variations in the power supply rating make significant differences in efficiency. The difference between a PSU rated at 80 PLUS and a PSU rated at 80 PLUS Bronze is about 2% to 5% depending on the load. This number only grows with better rated PSUs.

Other factors including the components of the computer. Recently, newer devices (CPUs, GPUs and motherboards) have been made with beyond significant generational improvements in efficiency. A top-of-the-line computer from 3 years ago simply cannot compete with some mid-range computers in terms of both power efficiency or performance. So, while sourcing older but cheaper components in the past may have been a good decision, nowadays, its not as clear cut.

Which components draw the most power?

How does the number of cores in a computer impact power usage?

You can't manage what you don't measure.
- Peter Drucker -

One famous quote attributed to Peter Drucker is that you can’t manage what you don’t measure. As power consumption becomes increasingly important, it’s incumbent upon all of us to both measure and manage it.