Choose the Right CAD Workstation Components

You've got a limited budget for new hardware — learn how to get the most performance bang for your buck!

Ah, a new computer. Nothing evokes that Christmas-morning feeling quite like a fresh, fast computer that boasts lots of open drive space. Too bad it only appears once every few years. As a CAD manager, you may play a major role in selecting that shiny new workstation hardware, or you may defer to your IT department. Either way, you need to understand how to specify the best-performing equipment for your users.

We'll start by breaking down the components of the workstation and emphasizing which part is most crucial for various CAD computing tasks. I am assuming that although you aren't necessarily an expert, you do have a working knowledge of computer components. Hopefully it’ll be clear that there really is no “best computer” for any given user, but if you know what to look for you can find the best computer for your specific needs and users. Here goes.

Priority 1: Cores

In any computer, be it a compact desktop, full-blown workstation, or notebook, the processing happens on the core(s). With the possible exception of a full-blown animation/rendering computer (more on this later), no single component has more to do with performance. Therefore, your purchase decisions should start at the core.

Multiple cores have become the norm in recent years, with four-core (quad-core) architectures like the Intel i7 becoming very common even in notebook computers. Of course, not all quad-core machines are the same. As an example, Intel Xeon quad-core machines are often built around chip sets that offer faster processing speeds, more cores, bigger data caches, and more RAM than most i7 machines (more on this later).

When you purchase a workstation, you are locking into a core architecture and will be stuck with it for the life of the computer (or at least the motherboard). Therefore the number and speed of cores you purchase is the most important aspect to specify. If you buy an i7 quad-core machine that supports a maximum of 8 GB of RAM now, you may not be happy with that decision in several years. Remember, you can upgrade RAM later, but if you aren’t happy with the number of cores you have now, you never will be.

Priority 2: RAM

To provide the cores with data to process, you’ll need RAM — therefore the amount of RAM is crucial for overall machine performance. Skimping on RAM sentences your computer to less-than-optimal performance, although you can upgrade the RAM later if you choose to install less than the maximum when you buy the computer.

Why would you scrimp on RAM instead of maximizing it from the get-go, you might ask? Well, what if waiting a few months to upgrade the RAM allows you to spend that money on more processing-core power now? In that case, the extra core power might be worth the short-term sacrifice when you consider the overall life of the machine. I’m not saying that scrimping on RAM is the best idea, but postponing the upgrade is a valid option if your budget is tight.

Here are a few other RAM rules of thumb to keep in mind:

• More RAM is better, so max out your machine if you can afford it. After processing cores, there is nothing more important to your machine’s performance.
• To maximize performance, make sure all RAM modules have the same speed rating, capacity, and ECC architecture. Failure to so will cause all RAM you install to perform at the specifications of the slowest module.
• Fill all RAM slots to move data through as many data channels as possible. For example, it would be better to have 8 GB of RAM installed as 2-GB modules in all four RAM slots rather than as 4-GB modules in only two slots.

Priority 3: Disks

Of course, no data can ever make it to the RAM and processor cores unless it is first read from a storage disk of some sort. The two options for disksinclude the traditional spinning magnetic hard drive and a new technology, an entirely solid-state drive (SSD) made of non-volatile RAM that retains data even when powered off.

SSDs are more expensive than hard drives, but they can deliver very high amounts of data to the processors and RAM on a continual basis, whereas hard drives deliver data in rapid bursts (via on-board caching) but slow down noticeably when you work with computing-intensive CAD tasks like rendering or simulation/analysis.

A simple way to gauge your need for SSDs is to watch the hard disk controller light or, if ambient sound levels are low enough, listen for the sounds your hard drive produces. If they reveal that the hard drive is almost always on while performing CAD tasks, that means you’re spending a lot of time waiting for your hard drive. And if you’re waiting on your hard drive, why bother spending all that money on cores and RAM? When you think of it that way, it's clear that SSDs make a lot of sense for heavy-duty CAD users that regularly manipulate big models.

With SSDs getting cheaper, they are at least worth your while to consider. A small SSD in combination with a large hard drive allows me to keep my active CAD files on the SSD for much faster rendering and analysis performance.

Priority 4: Monitors

It is hard to overstate how difficult it is to work in a visual design application with a small, low-resolution monitor. Almost any computer you buy now can displayimages at HD-level resolutions (1280 x 720 or higher) onto 24” form-factor LED monitors that really help you see what you’re doing. Of course, you can go larger than 24”, but with monitors of that size dropping below $200 there’s no reason to keep struggling with antiquated small monitors.

Another option to consider is a dual-monitor setup, which — for only a little bit more — allows you to view your CAD application on a large, high-resolution monitor while using spreadsheets, e-mail, and other applications on a smaller screen (perhaps the old monitor you already have). With multiple monitors you won’t have to switch tasks all the time, and you’ll be more productive.

Priority 5: Graphics Processor

You may notice that I’ve placed the graphics processor way down on the list, and may be wondering if I’ve made a mistake in doing so. Let me qualify my recommendations by saying that most CAD users don’t spend their whole workday making animations and renderings. Most CAD users are occupied with in dimensional modeling or even simple 2D, while seldom, if ever, performing analysis or rendering. While a BIM (building information modeling) user, mechanical designer, or civil engineer may well use shaded representations to assist in visualizing their 3D work, it isn’t high-end rendering.

For those who fit into the “most CAD users” category, the graphics processor is far less important than having fast application performance. After all, if you spend 10% of your day rendering and 90% designing, your computer should be set up to optimize productivity on CAD applications.

So how do you maximize application performance? With cores, RAM, SSDs, and multiple monitors, that’s how.

Now, if you’re one of the few who does spend many hours rendering, animating, or capturing motion-based output from your CAD applications, then by all means go for the high-end graphics processors that support your applications. Otherwise, you’re perfectly safe with a lower-end graphics processor of even embedded HD graphics included on most i7-based computers.

The bottom line is this: Put your money into the components that will make the user more productive. For most users, that isn’t the graphics processor!

Homework Assignment

Now you can complete your own hardware homework by exploring some web sites from major hardware providers (HP, Dell, etc.) and experiment with building machine configurations based on the points covered in this column. As you swap components, you’ll be able to see the cost impact and learn where you can afford to boost computer performance, where you can’t, and where your dollars will be most useful.

Summing Up

CAD managers always have a lot on their plate, and with IT taking over so much of the machine specification tasking in recent years, it's all too easy to let your hardware expertise slide. But if you want to get the right workstations for your users and get the best cost performance you can, it really pays to refresh your knowledge and share the purchasing responsibility with your IT department.

Your users will love you for it, your company will love the enhanced productivity, and IT won’t mind the helping hand. Until next time.