Updated September 24, 2023
If you use CAD software on a regular basis, either as a student, hobbyist or professional, you have probably wondered what specs your computer needs to run it. As with gaming or other intensive applications, computer hardware plays a huge role in performance for CAD software. However, an ideal setup for gaming or Photoshop is not necessarily good for Solidworks, and vice versa. If you invest in a new computer, you probably want it to be the right computer for the job. This blog post will walk you through the process of selecting the critical hardware components for a general purpose CAD workstation.
If you plan on building your own PC, buying a new/used/refurbished PC, or upgrading some outdated components for better performance, hopefully you will have a better understanding of what makes things tick after reading. It does not matter if you use Solidworks, Creo, AutoCAD, Catia, or Inventor – the same principles apply, and this guide is for you. Also, while I’m focusing on desktop workstations in this post, the same concepts apply to laptops/mobile workstations – just keep in mind that laptops don’t dissipate heat as well and provide less performance per dollar.
The core components for a CAD workstation (and any computer, really) are the CPU (central processing unit), the GPU (graphics processing unit, AKA graphics card), and RAM (random access memory). There are other components that are also important, such as storage, motherboard, power supply, and cooling system, but these are usually secondary considerations based on the core components you select.
Disclaimers: 1) While I know a lot about CAD workstations and the hardware involved, I’m a mechanical engineer, not a computer guru. I can’t, and won’t, give you specific advice on overclocking or explain the difference between Intel and AMD architecture. 2) I use affiliate marketing links on my blog. If you click on a link and buy that product, I might get a small commission fee from the sale.
The CPU
Photo Credit: Christian Wiediger via Unsplash.
The CPU is ultimately the most important part of any PC, and it determines how quickly programs and applications run. The two most important factors are 1) clock speed/clock frequency, measured in GHz, and 2) the number of cores. At risk of oversimplifying, the clock speed determines how quickly the CPU executes commands while the number of cores determines how many processes it can run simultaneously.
Most CPU models come in two main configurations: locked and unlocked. Locked CPUs are generally cheaper, while their unlocked cousins are slightly faster with out-of-the-box settings. However, unlocked CPUs can be overclocked for an additional 10%-20% performance increase, provided the right motherboard chipset and proper cooling. Even with a good setup, overclocking can cause some stability issues, so it’s important to decide if it’s worth taking that risk for a little extra performance.
So, what spec is more important for CAD applications, clock speed or core count? 3D modeling and drawing detail operations are generally single-threaded and only utilize one CPU core at a time, while rendering and simulations can take advantage of multiple cores through parallel processing. A general-purpose CAD workstation will benefit most from clock speed, and unless you spend a significant amount of time running simulations or rendering, you should aim for a CPU with high clock speed and moderate core count.
As an example, the Intel Core i9-13900K has 24 cores (8P + 16E) and can reach speeds up to 5.8 GHz, with an MSRP $589. On the other hand, the Intel Xeon W9-3475X has a whopping 36 cores but can only reach 4.8 GHz with an MSRP of $3739. If you spend hours every day rendering or running simulations, the extra 12 cores might be worth the money, but for general 3D modeling the W9-3475X will actually have poorer performance at a much higher cost.
TL;DR: If you do a lot of rendering or simulation, get a CPU with a lot of cores and a decent clock speed, such as the Intel Xeon W9-3475X. Otherwise, go with the best CPU that you can afford with the fastest clock speed and a moderate core count. Consider overclocking only if you have the time, patience, and money for an unlocked CPU, decent motherboard, and fancy cooling system.
My CPU Recommendations:
The GPU
Photo Credit: Christian Wiediger via Unsplash.
The GPU, or graphics card, determines how well graphics display, as output to a monitor. Programs like Solidworks break 3D models into tiny triangles, sort of like 3D pixels, which are processed by the GPU to display an image on your monitor. As you rotate or rebuild a model, the GPU has to recalculate those triangles to generate an updated image, or frame. Bigger models take longer to process or require more processing power to process in the same amount of time. As a result, once the GPU starts to bog down, frame rate decreases.
There is a lot of discussion about the best frame rate for computer applications, which depends on things like human perception and monitor refresh rate. Here’s the TL;DR version: When it comes to graphics cards 1) higher frame rates (measured in frames per second, or FPS) are always better, and 2) the difference between 200 FPS and 150 FPS might not be very noticeable, but the difference between 60 FPS and 10 FPS definitely will be.
Memory, bandwidth, clock speed, and CUDA core count are specs you will likely come across when shopping for graphics cards, but memory size (GRAM) will be one of the most important factors to consider for CAD. In terms of those tiny triangles mentioned earlier, bigger models will require more GRAM. For example, if you only model individual parts and work on simple 2D drawings, a 2GB GPU will work just fine for you. If you work with large assemblies (hundreds or thousands of parts), a 4GB or 8GB GPU will probably suit you better. For huge assemblies with hundreds of thousands or millions of parts, you better get the best GPU on the market (e.g., Nvidia Quadro RTX 6000 at 24GB).
One of the biggest questions I see is whether to go with a gaming graphics card, or a dedicated workstation graphics card, such as the Nvidia Quadro or AMD FirePro series. Without getting into nitty gritty details, workstation graphics cards are designed specifically for applications like Solidworks, AutoCAD, and Creo, and provide better stability and compatibility than gaming cards. You might be able to get a gaming card that can run Solidworks, but the best overall performance for the money almost always comes from workstation cards.
TL;DR: Make sure to get a dedicated workstation GPU, such as Nvidia Quadro or AMD FirePro, with sufficient GRAM capacity for the size of models that you work with.
My GPU Recommendations:
RAM
RAM, often just referred to as memory, is another core part of any workstation PC. As with GPU memory sizing, the amount of RAM you need is determined by the tasks you perform and the size of the models/assemblies you work with. For CAD applications, 32GB is usually considered the bare minimum. I work with complex parts and large assemblies on a regular basis, so for me 64GB is the sweet spot. The bottom line is that you won’t notice any performance increase from getting extra RAM, but not having enough will really throttle productivity. I frequently hit 32GB+ RAM utilization, so while 128GB wouldn’t make any noticeable difference, I would be very frustrated on a daily basis if I only had 32GB.
Photo Credit: Luan Gjokaj via Unsplash.
As of October 2020, there are two types of RAM that you will see: DDR3 and DDR4. DDR3 is older, so a computer that was built before the mid 2010’s will be configured for DDR3. DDR4 is newer but has been around for long enough that I expect it will be replaced with DDR5 eventually. The bottom line is that if you have a motherboard with DDR3 RAM, you won’t be able to upgrade to DDR4 without tearing out your motherboard and getting a new CPU while you’re at it. DDR4 has faster clock speeds, so it has some performance advantages.
2023 Update: DDR3 is now essentially obsolete, and DDR5 has replaced DDR4 in newer systems. If you are building a new system, go with DDR5 RAM. If you are upgrading an existing system, it might be running DDR4 RAM. Bottom line: your motherboard will determine what type of RAM you can use, so make sure that you know your specs before ordering anything!
Speaking of clock speed, in addition to RAM capacity, clock speed is another spec to pay attention to, along with timing. Higher clock speed and lower timing are both good, as a rule of thumb. For example, the RAM that I put in my 2020 build has a clock speed of 3200MHz and CL 16 timing. If you are buying an already built workstation, clock speed and timing is probably out of your control, so just focus on capacity. If you are building or upgrading, find some RAM with the right capacity for your application with the lowest clock speed/timing ratio that you can find for the money from a reputable manufacturer and call it good.
TL;DR: RAM capacity should be based on your workload, and while having extra RAM won’t improve performance, having too little will be a major bottleneck. As far as speed and timing go, pick a capacity and a budget and find a RAM kit with the highest speed and lowest timing within your budget.
My RAM Recommendations:
Final Thoughts
If you’re looking for a more comprehensive list of components needed to build a CAD workstation, check out the links below:
As you surely know by now, there is a lot of information on this topic, and I could have easily spent this entire post talking about just one component. I could also spend quite a bit of time discussing some of those less critical, but still important topics, like cooling, power supplies, and motherboards. I did not mention benchmarks at all either. Some of those things might fit in to future blogs posts eventually, but in the meantime, here are some additional resources to help you as you decide on the right build for your next CAD workstation:
Did you find this information helpful? I’d love to hear your thoughts! You can email me directly at dan@schanerdesigns.com or comment down below.