workstation special report
We need to talk about energy No one wants their workstation to go slower. But in a world obsessed with bigger, better, faster, should we be paying more attention to how much energy they consume? asks Greg Corke It feels a little hypocritical to kick off this For the CPU, expect to see 100% usage Workstation Special Report with some when rendering. In CAD, it’s much lower, advice on how to save energy. After all, as fewer cores are used. For the GPU, realI’ve spent the last two months testing time visualisation and GPU rendering will workstations with some of the most also use 100% of GPU resources – again, demanding design and visualisation this is usually much less for CAD. tools. The fastest processors get lauded, All processors have a sweet spot where but they are almost always the biggest they run most efficiently. After that point consumers of electricity. there are diminishing returns, and you’ll We all know we need to use less energy need to pump a lot more power into the to protect the environment, but there’s chip to increase frequency and therefore nothing like a global energy crisis to performance. As a result, running CPUs at focus the mind. The fact is that the energy slightly lower frequencies can save power consumption of processors has been rising without slowing things down too much. steadily. Today we have mainstream CPUs Windows has built in power settings that draw over 250W at peak and high- to control how much the CPU boosts. To end GPUs that hit 450W. explore the impact of this And even though we’ve had we rendered an 8K scene the coldest snowy December in KeyShot. With a highin years, you can still warm performance power plan on a home office with a few a Dell Precision 5470 mobile high-performance machines. workstation with the 45W Thank goodness we didn’t Intel Core i7-12800H CPU do the Workstation Special (see page WS28) it consumed Report this summer! 0.025 kWh and took 18 Performance per watt has mins 18 secs. The same scene always been a metric for rendered with an energy workstations, but how many saving power plan used Don’t waste of us have really purchased a 0.022 kWh and took 24 mins machine with that in mind? 32 secs. Halving the number compute We buy our light bulbs and of cores had the opposite resources. appliances based on energy effect, increasing power Some viz tools usage to 0.033 kWh and efficiency, run our washing machines in eco mode. Some will continue taking 36 mins 31 secs. of us even drive our cars at Of course, some processors to render the 56 mph — if the authorities are more power hungry than viewport when others and the new 125W+ have cleared the snow. idle, so switch Intel Core i9-13900K (see To learn how to save energy, we first need to understand them off when page WS04) is one of the how much our workstation The Boxx Apexx not required hungriest. consumes. The easiest way to 4, for example (see page do this is with a power meter. WS17), used 0.042 kWh Simply plug it into a mains to render the same scene, socket, then plug your workstation directly although it did this in 6 mins 09 secs. into that. It measures how much energy But wouldn’t be nice if we could have our your entire workstation consumes in real- cake and eat it too? Save energy and still time, in watts and kWh. Fancier ‘smart’ get the same (or very similar) performance devices can track usage through an app. out of your workstation. Well, you might While memory, storage, motherboard, just be able to do that by undervolting PSU, and fans all use energy, the CPU and your processor. Modern CPUs allow you GPU are by far the biggest consumers in to lower the amount of power that they your workstation. To understand how receive, but without necessarily slowing these work in relation to your workflows, them down. It’s generally reserved for you can get a pretty good idea with people who know what they’re doing, so Windows Task Manager > Performance. proceed with caution, or ask your custom
workstation provider if that’s an option. The temptation when speccing out a workstation is to go for as powerful components as you can afford. With ray tracing, more performance generally means lower render times, so there’s a tangible benefit. However, for real time 3D there is a danger of paying for performance you simply don’t need. If your viz datasets aren’t that complex and you can smoothly navigate your scene with a 70W GPU like the Nvidia RTX A2000, do you really need the 200W Nvidia RTX A4500? Your workstation will consume more power and you probably won’t notice a difference. Another tip is don’t waste compute resources. Some viz tools will continue to render the viewport when idle, so switch them off when not required. This includes Unreal Engine (GPU), Twinmotion (GPU), KeyShot (CPU / GPU), Solidworks Visualize (CPU / GPU) and others. Also ask yourself some questions: does your render really need that many passes? Do you really have to have it back so quickly? Could you render at a lower resolution? Could you use AI denoising? Finally, hybrid renderers can use both GPU and CPU resources, but because the code is generally optimised for the GPU, the contribution of the CPU can be quite small. It can still use lots of energy though, so disable it in the settings.
www.AECmag.com
January / February 2023
‘‘
’’
WS03_AEC_JANFEB23_Comment.indd 3
Final thoughts With new technology, pushing components to their limits seems a natural thing to do. But this not only increases energy usage of the workstation but can also have a knockon effect on our working environment. This winter, the heat given out by the powerful machines tested for this report was certainly welcome. In summer, less so. It’s not only your workstation fans that need to work harder, it’s your office air con as well. Of course, we all have jobs to do and deadlines to meet. But some small adjustments to your workstation config, workflows, habits, or purchasing decisions can make a big difference. Driving at 56 mph down the M1 motorway might not feel that exciting, but if it helps save you money and lessen your environmental impact, there’s much to be said for slow and steady win the race. WS3
25/01/2023 16:59