I recently read an article by an Intel product manager on the need for “ECC” (error correction code) memory in CAD workstations. From the article: “Corrupted data can impact every aspect of your business, and worse yet you may not even realize your data has become corrupted. Error-correcting code (ECC) memory detects and corrects the more common kinds of internal data corruption.”
For some reason this triggered my memory of the sudden-acceleration Toyota Prius incident from 2010. The popular press latched on to the idea that cosmic rays were screwing with the electronics in the Prius. While theoretically possible, the probabilities of this were astronomically low. It did however, make for a great story and the FUD (fear uncertainty doubt) caused Prius prices to temporarily plummet and sales come to a crawl.
Back to ECC memory and CAD systems. Is there really a need for ECC memory in CAD or is it just FUD marketing to upsell hardware and make products sound more valuable than they really are? I decided to do a little research.
Who needs ECC memory and what is its role in professional & CAD workstation computing?
Naturally occurring cosmic rays can and do cause problems for computers down here on planet Earth. Certain types of subatomic particles (primarily neutrons) can pierce through buildings and computer components and physically alter the electrical state of electronic components. When one of these particles interacts with a block of system memory, GPU memory or other binary electronics inside your computer, it can cause a single bit to spontaneously flip to the opposite state. This can lead to an instantaneous error and the potential for incorrect application output and sometimes, even a total system crash. However, the theoretical chances of a single bit error caused by a cosmic ray strike on your PC or workstation’s memory is fairly rare — only about once every 9 years per 8GB of RAM, according to recent data.
ECC technology — used as both system RAM, and in devices such as high-end GPUs — can reliably detect and correct these errors, reducing the odds of memory corruption due to “single bit errors” down to about once every 45 years for 8GB of RAM. Of course, just like everything else in life there are always tradeoffs. ECC memory is typically up to 10% slower and significantly more expensive than standard non-ECC memory.
Because the odds of a cosmic ray strike increase in direct proportion to the physical amount of memory (and related components) inside a computer, this is a real concern for large scale, clustered supercomputing and other environments where computing tasks often include high-precision calculation sets that can take days or even weeks to complete. In the case of supercomputer clusters, which often contain hundreds or even thousands of connected computer nodes and terabytes of memory, the odds of cosmic ray strikes on the system are much more likely — and much more costly. Restarting a week-long calculation on a supercomputer can cost a facility many tens of thousands of dollars in lost time, electricity and manpower —not to mention lost productivity.
But for even very beefy PC CAD workstation configurations with loads of RAM on board, you are probably not at imminent risk from problems caused by cosmic ray strikes and the resulting single bit errors. Over the course of your work, you are much more likely to endure system crashes or application hangs dues to failing components, power fluctuations and software bugs than due to cosmic ray strikes. Additionally, many applications in the desktop design and engineering space can actually endure a single bit error without negatively impacting the computing process or product. For example, if the color or brightness of a single pixel on a display monitor is changed due to this type of memory corruption on the system’s GPU, nobody will ever see or notice it. There are many such examples of this type of error not really impacting ones everyday work.
This said, many leading technology manufacturers are enabling their high-end products with ECC memory for compute-heavy (especially clustered supercomputing) applications where the benefits of using error correcting memory outweigh any comparative speed/cost drawbacks. AMD for example, has engineered their new AMD FirePro W9000 and FirePro S9000 ultra-high-end GPU cards to include ECC memory which can selectively be enabled by the end user and used for many advanced computing purposes where rock-solid stability and protection from space rays is crucial.
Author: Tony DeYoung
Where do you begin your quest for the right workstation? This particular hardware search should start with your software.
Let’s be real: Nobody relies on just one application over the course of a day. We’re all bouncing between disparate tasks and windows. But for the majority of CAD professionals, there is one application — or maybe a couple — that consumes the bulk of your hours at the desk. What’s the app that dominates your day? Got it? Now hit the web site of the software developer and find the minimum and recommended system requirements for your killer app. AutoCAD users can find this information at http://usa.autodesk.com/autocad/system-requirements.
Minimum is the Starting Point Only
In most cases, an application’s minimum requirements set an extremely low standard, as the software vendors begrudgingly must address the least common denominator of the installed base. We don’t recommend you follow these guidelines, but it’s worth making a note of the minimum graphics, system memory and CPU requirements. On the other hand, it’s highly likely that any new workstation on the market today will meet or exceed these numbers.
More interesting is the list of recommended or certified hardware. For SolidWorks, Dassault Systèmes (as of this writing) specifies a minimum of 1 GB RAM, but suggests 6 GB. Well, if you go with 1 GB, you’ll be sorry — even 6 GB isn’t necessarily the best choice, depending on your budget, and especially given the incredible amount of gigabytes/dollar that can be had today.
Similarly, Autodesk isn’t going to stop you from running a PC gamer graphics card, but the company will tell you which cards are optimized for performance and built for reliability when it comes to supporting AutoCAD or Autodesk Inventor.
Increasingly, the only CAD-certified graphics cards are professional-brand NVIDIA Quadro and AMD FirePro. That’s because software developers have consistently seen the fewest bugs and problems with cards that, like the system overall, have been exhaustively tested and tuned for professional workstation applications. In fact, the major CAD software developers will help you address issues related to running a Quadro or FirePro card, but they dedicate no support cycles to fixing bugs on consumer-class hardware.
Reality capture is a boom business for the building industry. With roughly 5 million existing commercial buildings in the United States alone, it’s easy to understand why. Laser-scanner-based reality capture is the dominant methodology used today to accurately capture the 3D state of an existing building. However, the typical laser-scan-based point cloud is in the hundreds of millions of 3D points, sometimes even going into the billions of points. With this additional data overhead on top of an already dense Building Information Model, it’s important to optimize your workstation hardware to deliver a productive user experience.
Finding the Bottleneck
Under the hood, Autodesk Revit utilizes the PCG point cloud engine to rapidly access the 3D points contained in point cloud and retrieve points to be displayed in the current Revit View. Since the typical point cloud dataset is so large, a workstation’s RAM is insufficient to be used as the means for access by the PCG engine in Revit. Instead, the disk drive is used for access, while a small amount of System RAM and Video RAM is used for the current Revit View. Thus, the hard drive is commonly the limiting factor for point cloud performance, rather than system RAM, CPU, or GPU.
Learn the Options
With data access a common limiting factor to the performance of the Revit point cloud experience, let’s discuss the options available to deliver the best experience. There are two primary types that are found today: spinning platter and solid-state drives.
- Spinning platter drives are the traditional hard drive technology, and are found in most computers today, as they deliver the best balance of storage capacity, read/write access speed, and cost.
- Solid-state drives (SSDs) are relatively new technology, contain no moving parts, and are generally much faster at reading and writing data than typical spinning platter drives.
In a structured comparison completed by the Revit product team, we found the following results when comparing typical versions of these Disk Drive types:
Reap the Benefits
Based upon this investigation, we would highly recommend that those looking to optimize their Revit workstations for point cloud use install an SSD for at least the local storage of the point cloud data. While you will also achieve additional benefits from running the entire OS on your SSD, a significant performance boost can be achieved through the retrofit of a ~$200 SSD to an existing workstation.
Author: Kyle Bernhardt, Product Line Manager, Autodesk Building Design Suite
Memory size and speed, or RAM, can significantly impact performance, and depending on the application, could influence throughput more than anything else in your CAD workstation. Usually there’s a sweet spot. To find it, start with the minimum recommendation for your primary software, then get a feel for how much more memory you’ll get with incremental spending.
Performance versus Budget
To achieve solid performance within a reasonable budget, that sweet spot today is likely between 6 GB and 16 GB of DDR3 1333-MHz RAM. DDR3 is third generation, dual-data rate memory technology, with Intel’s current platforms centered on 1333-MHz clock frequency — and it’s really your best memory option these days.
Also pay attention to how many of your system’s dual inline memory module (DIMM) slots are taken up by the system memory. This should be clear from the system specs and from the system configurator when purchasing a system online. For example, 4 GB might be specified as “1333 MHz, DDR3 SDRAM, ECC (4 DIMMs),” meaning that four slots are occupied (out of the total number of slots specified in the model’s spec page or datasheet). Ideally, you’ll want to leave some DIMM slots empty so you can give your system a mid-life memory upgrade if needed. Depending on the density you’ve chosen, leaving empty slots often involves no additional cost.
Error Correcting Code
And what of Error Correcting Code (ECC), an upgrade that typically allows single-bit memory errors to be detected and corrected? New Xeon processors offer integrated ECC, but with other processors it’s an added expense. For most CAD applications, ECC is certainly valuable but not essential. If the added cost is modest and doesn’t sacrifice performance — sometimes the DDR clock frequency must drop to accommodate ECC — go for it.
This series focuses on helping our readers understand what CAD workstations cost and how much they are going to have to spend to find a machine that meets their CAD production needs. The first part focused on entry-level systems. This post will discuss mid-range ($2,500 to $7,000) and high-end (more than $7,000) systems.
Mid-Range and High-End
Stepping up to the mid-range and high-end, you’ll typically find dual-socket Intel Xeon processors along with full tower enclosures to handle more slots and drive bays. Spring for a dual-socket system and you’ll get twice as many CPU cores, twice as much memory bandwidth, and twice the memory capacity.
Some OEMs are going to great lengths to show off the enhanced speed of processors and increased capacity of both graphics cards (for multi-monitor or high-performance computing support) and larger storage capabilities. For example, BOXX’s top-end 4800 and 8500 series workstations feature overclocked CPU performance that provides a 25% higher frequency rate — that is, an Intel 2600k (Sandy Bridge) processor running at 4.5 GHz instead of 3.4 GHz. These workstations also provide support for as many as eight drive bays and an incredible seven PCI Express slots, allowing users to populate 18 TB of total storage and house seven single-width or four dualslot graphics cards.
But there’s more to be had at the upper end of the market, as vendors are taking a page from Apple’s book and investing an impressive amount of time and money to engineer hardware aesthetics and ergonomics, resulting in advances such as tool-less and (almost) cable-less designs; carefully designed air flow; and custom, workstation-specific, high-efficiency power supplies.
Start with Your Base Requirements
So do you really need a mid-range to high-end workstation? Will an entry-level CAD workstation do? The place to start is the base requirements for your CAD software of choice, then plan a system purchase accordingly. Note that this information makes a good starting point for configuring your workstation. We consider that the baseline, and you probably want some room to grow for software upgrades.
Also if you are doing any 3D modeling, look for faster and more capable processors, more RAM, more available hard disk space in addition to free space required for installation, and a graphics display adapter capable of at least 1,280 x 1,024 resolution in true color. The graphics card needs to have 128MB or more memory, support for Pixel Shader 3.0 or greater, and Microsoft Direct3D capabilities. (Again, consider these a starting point.)