Answers to Your Workstation Questions

There are a variety of factors to consider when selecting the optimal engineering workstation configuration. Desktop Engineering questioned leading CAD value-added resellers (VARs) to discover how they guide their clients through the hardware selection process.

Q: What factors (such as model size, use of simulation and photo-realistic rendering) go into determining a hardware recommendation for CAD users? 

Adrian Fanjoy, Computer Aided Technology Inc.

A. Adrian Fanjoy, technical services manager, Computer Aided Technology Inc. (CATI), SolidWorks Reseller: Photo rendering and simulation have a big impact because they would determine whether or not you go with a system with more than four cores. That drives up the cost of the machine drastically.

After that, we generally look at the size and complexity of the models and the assemblies themselves.

The number of cores when dealing with just SolidWorks is pretty standard; you go with four cores no matter what. What we are really doing is adjusting the amount of RAM and the processor speed. No matter how big the assembly is you will benefit from an increase in processor speed.

A. Chris Teague, senior applications engineer, Saratech, Solid Edge Reseller: Model size and the size of the assemblies. And then, of course, whether they are going to run FEA (finite element analysis), detailed rendering or complex analysis work. Those customers will need more computer horsepower.

Matthew Burke, M2 Technologies.

A. Matthew Burke, principal and CEO, M2 Technologies, Autodesk Reseller: The two most obvious factors are how large the assemblies are and how complex they are. Beyond that, are they doing FEA, CFD (computational fluid dynamics) analysis, or using a CAM package on the same workstation? More subtle factors include how often they upgrade their engineering hardware. If a customer has a regular schedule, you might not recommend the highest end machine; but if a customer only upgrades hardware every three to five years, they really need to purchase as much horsepower as they can afford today.

Q: Are there any common misconceptions about hardware needs you routinely run across with CAD customers?

A. Fanjoy: People who haven’t really done their homework assume a more expensive machine is what they need, or assume that the best graphics card possible is what they need. They may buy a dual-processor machine and find they don’t need the second processor. There’s a general tendency to over buy.

Chris Teague, Saratech.

A. Teague: The biggest one is that people confuse the number of CPUs with single-thread performance. With CAD, even with FEA, single-thread performance is more important. I’ve seen people get a huge number of cores with a low clock speed. There are very few applications that take advantage of a huge number of cores.

A. Burke: Yes, that all machines are the same. I also think customers don’t understand that part complexity is as important as assembly size with regards to performance. I once had a customer who didn’t understand why his part with over 250 unique individual holes, all at unique angles, all with unique features, was causing a significant degradation in performance.

Q: What questions do you ask CAD users when trying to determine their hardware needs?

A. Fanjoy: We like to know what they are currently using and what their comfort level is. Waiting for a minute and a half for something to happen might be OK for me, but you may need to have it happen in 30 seconds. Finding out how disgruntled they are with their hardware helps us find a path to make them more comfortable.

A. Teague: We find out what software they are running, how many different packets they run, if they do FEA, if they have a high-end CAD system or low-end system. And then we ask how big the assemblies are and what other types of analysis they are doing. Budget is also a big driver.

A. Burke: If the customer will let us, we actually like to see examples of their parts and assemblies.  Beyond that, we work with the customer to really understand how complex their parts are and how large their assemblies are. Additionally, we consider what other things the engineers do today or could be doing tomorrow.

Q: Would you recommend a multi-core processor for a CAD user? If not, what other activities (simulation, rendering, etc.) would warrant such a recommendation?

A. Fanjoy: Yes, four cores, and only four cores. No more than. The caveat would be if they are going to use other applications simultaneously with CAD, they might need more cores.

A. Teague: I do recommend multi-core, but not in large numbers. For most CAD users a quad-core at a higher clock speed is all you need. Most users don’t need that many cores. Even with FEA, only some of those systems need large numbers of cores. Often they are better off with a faster SSD (solid-state drive), faster memory and a higher clock speed.

Q: Would you ever recommend a workstation with multiple processors for a CAD user? If not, what other activities (simulation, rendering, etc.) would warrant such a recommendation?

A. Fanjoy: Not unless they were doing a lot of other things like simulation and photo rendering. Especially photo rendering. Even with simulation, you can get a single processor now with eight cores. With all the simulations we’ve tested, after six cores the performance curve flattens out and you don’t get a lot of benefit. For photo rendering the benefit is almost unlimited as you add cores.

A. Teague: If it’s in their budget I would. You take a big hit in price to do that. For clients that have a large budget, we put in multiple processors because then they’re set up to do toolpaths and FEA. At a lower budget, that’s not the first thing we need to do.

A. Burke: It doesn’t happen very often strictly for a CAD user, but we have made the recommendation before based upon the unique needs and uses of a client. More typically we recommend multiple processors for those running complex CFD or FEA studies or doing high-end visualization, rendering or animation projects on a regular basis.

Q: How do you determine the amount of RAM a CAD user should invest in?

A. Fanjoy: It’s not too detrimental to over-buy. We don’t recommend anybody get under 8GB, because it’s almost a given anyway. But do you need 16GB or 32GB? Typically for large assemblies, 16GB is enough, and for super-large assemblies they may need 24GB to 32GB, but those are gigantic assemblies of 15,000 to 20,000 components or more.

A. Teague: The rule of thumb on that is we don’t recommend anything less than 8GB for anybody. We try to push everybody to 16GB, because that’s a general purpose number. If they are running larger assemblies, then 32GB on the desktop is good. More that that is for guys running dedicated servers.

A. Burke: We try and keep this simple: put as much RAM in as your budget will allow.  Certainly there are published guidelines available for both minimums and recommendations, but they generally don’t take into account the other applications that are going to be up and running.

Q: What processes do you recommend be carried out on an SSD vs. a traditional spinning hard disk?

A. Fanjoy: At this point, the only thing we recommend a traditional hard disk for is massive storage. If you use a PDM (product data management) system, and you’re operating with local cache, and you keep that clean and keep maintaining that so you don’t overburden it, a small 240GB SSD should be fine for any user.

A. Teague: We try to go SSD when we can and when the budget allows. You can get a smaller SSD for the boot drive, and if you need a larger amount of space you can do a traditional hard drive for data. At least get an SSD for boot. If the budget allows, then we have configured systems with four SSD drives in a RAID array for data, and a smaller one for boot.

A. Burke: In particular, FEA and CFD benefit a great deal with an SSD drive. SSDs have come down considerably in price so they almost always tend to be worth the investment in a CAD workstation because they are simply so much faster.

Q: In your opinion should a CAD user invest in a top-of-the-line, mid-range, or entry-level graphics card, or are integrated graphics sufficient? 

A. Fanjoy: That’s really going to depend on what you are doing. There is a point in just a couple of circumstances where entry-level graphics aren’t going to do what you need to do. The vast majority of our users would get away with onboard graphics just fine, at least that’s what my testing is showing. Areas where you’d need to look at a mid-range card would be with highly faceted models that have intricate details, and I mean immense amounts of small detail. What we’ve found is that as assemblies get larger, the ability of the graphics card to keep up with the data becomes a problem. If there’s degradation, you can always lower the level of detail in the model to accommodate for that and still get smooth rotation. Onboard graphics will work for even more situations if you are willing to sacrifice that level of detail while spinning the model.

A. Teague: We don’t ever recommend integrated graphics, because we have had so many problems with them not running OpenGL well. All the tools are running OpenGL, and the only cards that are tuned to that are the professional cards. There’s no reason to not go top-of-the-line for graphics except for budget. That’s an easy thing to upgrade later.

A. Burke: This is a difficult question to answer without additional context. Generally speaking our typical recommendation is a mid-range card unless we know, through qualifying, the type of design and work occurring would substantially benefit from a top-of-the-line card. Usually we say, save money here and invest in more RAM.

Q: Do you recommend professional workstations for CAD or are consumer-class PCs sufficient?

A. Fanjoy: The only time we tell people that a consumer-class PC is sufficient is if they are using a home-use license to build a deck at their house. Everything else should use quality graphics.

A. Teague: We do recommend professional workstations, because of the OpenGL issue. Consumer machines use consumer-class cards, but DirectX drivers aren’t as well tuned for OpenGL.

A. Burke: CAD is expensive, and designers and engineers are expensive—give them a machine with the architecture capable of allowing them to perform their jobs efficiently.  To put it another way, don’t ask Jeff Gordon to win at Daytona in an SS sedan from the local Chevy dealer.

Q: Is there a rule of thumb for how long a CAD user should wait before investing in a new workstation?

A. Teague: The general rule of thumb is three years, but that can depend on a lot of things. Did you buy at the high end three years ago, or did you get a cheap workstation? After three years look around and see what the technology is now vs. what you bought. Even if the hardware isn’t obsolete, a fresh install of Windows might make things faster.

A. Burke: Technology evolves at a very rapid pace, but for most folks the decision on hardware investment is happening on a corporate IT level so they have little control over it. If they do, we try and tell customers they should be on a two- or three-year upgrade cycle. Much longer than three years, we start to see the hardware becoming a constraint to the users.

Q: In your opinion, what hardware investment (faster/multi-core processor, more RAM, graphics card, SSD) would return the best ROI for a CAD user and why?  

A. Fanjoy: That’s a tricky question because it depends. If you’ve got not enough RAM on the machine, your biggest bang for your buck is going to be RAM every time. It really depends on what the deficiency is. You have to have enough RAM, four cores, the fastest cores you can get, the graphics card has to be supported and then you need SSD. I would go in that order.

A. Teague: Probably going with SSD. If you upgrade to SSD for boot, then everything loads faster. More RAM is probably number two.

A. Burke: This is really dependent on what each customer is doing and I think the best answer is a blended approach. RAM is the first area we tell folks to invest. That said, we are always going to recommend a multi-core processor and a mid-range graphics card.  From there, upgrade your RAM and probably add on an SSD drive so when you have to utilize virtual memory, you are getting the fastest response possible.

Q: What type of CAD user could benefit from virtualization or cloud-based services?

A. Fanjoy: That’s not a CAD question as much as it’s a corporate policy question. As cloud technology and virtualization improve, CAD is going along for the ride. You don’t ask if the CAD user can benefit from it, but instead you ask if the business can benefit.

A. Teague: Certainly the guy who is running part-time CAD and can’t justify buying the software and hardware all at once. Smaller companies that need site-wide collaboration across the country and want common file storage, but don’t have the IT department to set that up. It’s also good for overflow needs, if you need four or five extra seats for one week. Also, if you are running a big analysis job, but you don’t want to buy a machine because you only need it for a week.

A. Burke: Imagine a CFD study that takes four hours to run on your workstation, and you want to do 50 of them. Simple math tells me it is going to take five weeks or more do each of these. Now imagine setting up these 50 studies to run on the cloud and getting an e-mail in four hours that all 50 are available. That elastic computing capacity is the real power of the cloud. So the easy answer is, any CAD user doing computationally intensive work can benefit from offloading that to the cloud. Beyond that though, the cloud services offer a great way for organizations to work more collaboratively with internal teams, customers and vendors.

More Info

• Computer Aided Technology
• M2 Technologies
• Saratech