With an overclocked six core ‘Coffee Lake’ Core i7 CPU and a well engineered compact chassis, this is an impressive CAD workstation but it does come at a premium, writes Greg Corke

Ten years ago, almost all CAD/BIM workstations came with a quad core CPU. If you wanted more cores, say to cut render times, you needed a specialist CPU and much deeper pockets. You also had to accept that performance in single-threaded applications like CAD would fall, due to a drop in GHz.

In 2018, things have finally changed. The new Intel ‘Coffee Lake’ Core i7-8700K is the first mainstream Intel processor to feature six cores. And despite having 50% more than its predecessor, the ‘Kaby Lake’ Core i7-7700K, it should also deliver a small performance improvement in single threaded CAD/BIM applications.

The Core i7-8700K has a base frequency of 3.7GHz, at which all six cores can run, but is designed to turbo up to 4.7GHz in lightly threaded workflows. This is a much wider frequency range than the ‘Kaby Lake’ quad core i7-7700K (4.2GHz – 4.5GHz) but becomes irrelevant in the Apexx S3, the latest workstation from custom system builder BOXX.

BOXX has overclocked the Core i7-8700K so that all six HyperThreaded cores run at 4.8GHz, all of the time. This makes a big difference in CPU rendering applications.

The APEXX S3 completed our Luxion KeyShot render test 38% faster than the overclocked 4.6GHz Core i7-7700K Scan 3XS workstation we reviewed in March. Previously, in order to get this level of rendering performance, you had to go for a specialist overclocked Intel CPU with 8 cores or more, which was significantly more expensive and had a lower clock speed.

This is a welcome boost to users of CAD or BIM tools who rely on rendering as a key part of their workflow. The emphasis on CAD/BIM is important here, as this is where the Apexx S3 excels. Indeed, it set a new record in our SolidWorks IGES export test, which uses a single CPU core to process a complex CAD assembly.

Our test machine was kitted out with 32GB DDR4-2666MHz memory, which should be a match for very complex BIM models. But if you frequently use multiple applications as part of your design workflow, then it can go up to 64GB, distributed across 8 DIMMs.

In order to push the Core i7-8700K beyond its stock clock speed, BOXX has used an enterprise-class closed loop water cooling solution which connects via a flexible pipe to a large radiator at the front of the machine, cooled by two fans. With air drawn in at the front and expelled at the rear of the machine this does mean some of the heat extracted from the CPU is pushed back into the chassis. However, while fan noise was noticeable, we found it to be perfectly acceptable throughout all of our testing – although the RPM of the fans cycled up and down every 10 seconds or so during our KeyShot renders, which some might find annoying. Incidentally, this didn’t happen in V-Ray, where it was consistent.

Product specifications

■ Intel Core i7-8700K (overclocked to 4.8GHz) (6 cores, 8 Threads)

■ 32GB (2 x 16GB) DDR4 2,666MHz

■ Nvidia Quadro P2000 (5GB) (376.84 driver) or Nvidia Quadro P4000 (8GB) (376.84 driver)

■ 512GB Samsung 960 Pro M.2 NVMe SSD

■ ASRock Z370 Taichi

■ 174 x 388 x 452mm / N/A

■ Microsoft Windows 10 Pro

■ 2 year return to base (other options up to 5 years on-site)

CPU benchmarks (single threaded) - Seconds (smaller is better)

■ SolidWorks 2015 IGES export: 83

CPU benchmarks (multi-threaded) - Seconds (smaller is better)

■ Luxion KeyShot 6.1 render test: 363

■ V-Ray CPU rendering benchmark (CPU): 79

GPU compute benchmark - Seconds (smaller is better)

■ V-Ray render benchmark (GPU): 177 (Quadro P2000) 106 (Quadro P4000)

3D graphics benchmarks (3D CAD) - Score (bigger is better)

■ SPECapc for SolidWorks 2015 (shaded + edges): 7.25 (Quadro P2000) 7.55 (Quadro P4000)

■ SPECapc for SolidWorks 2015 (RealView + shadows): 12.60 (Quadro P2000) 13.43 (Quadro P4000)

■ SPECapc for SolidWorks (RealView + shadows + AO): 28.64 (Quadro P2000) 35.18 (Quadro P4000)

■ SPECapc for PTC Creo 3.0 (shaded + edges): 11.75 (Quadro P2000) 11.93 (Quadro P4000

■ SPECapc for PTC Creo 3.0 (reflection): 15.98 (Quadro P2000) 17.13 (Quadro P4000

3D graphics benchmarks (design viz) - Frames Per Second (FPS) (bigger is better)

■ LumenRT (hotel model) (FPS): 36 (Quadro P2000) 50 (Quadro P4000)

■ LumenRT (roundabout model): 13.5 (Quadro P2000) 21 (Quadro P4000)

■ Autodesk LIVE (Villa Enhanced model): 92 (Quadro P2000) 146 (Quadro P4000

■ Autodesk VRED Professional (AA off):33 (Quadro P2000) 53 (Quadro P4000)

■ Autodesk VRED Professional (AA medium): 18 (Quadro P2000) 29 (Quadro P4000)

■ Autodesk VRED Professional (AA ultra high ): 18 (Quadro P2000) 29 (Quadro P4000)

3D graphics benchmarks (VR) - Frames Per Second (FPS) (bigger is better)

■ VR Mark (Orange): 115.77 (Quadro P2000) 184.88 (Quadro P4000)

■ VR Mark (Blue): 19.71 (Quadro P2000) 33.17 (Quadro P4000)

■ VR Mark (Cyan): 62.22 (Quadro P2000) 100.12 (Quadro P4000)

The chassis is nicely designed with an angled I/O panel front and top giving easy access to four USB 3.1 ports (there are also four USB 3.1 and two USB 3.0 at the rear). This leaves the entire front façade free for uninterrupted air flow. To stop dust getting in, there is a removable air filter.

The chassis is custom-made in Texas from aircraft-grade aluminium. I’m no aerospace engineer, but it’s obvious that it has a strength and rigidity beyond that of off-the-shelf cases. It’s also notably smaller than many of the expandable overclocked machines we review at AEC Magazine.

One of the reasons for this is that BOXX has put two 3.5-inch drive bays at the top of the chassis instead of the front. There is also no optical drive. Our test machine came with a single 512GB Samsung SSD 960 Pro, one of best workstation class M.2 NVMe SSDs on the market. It is housed directly on the ASRock Z370 Taichi motherboard, which also has two additional M.2 slots, so there are plenty of storage options.

Graphics in our test machine were provided by a single Nvidia Quadro P2000 GPU, an excellent choice for 3D CAD. The Apexx S3 managed to smoothly navigate every Revit, SolidWorks, and PTC Creo model we threw at it at FHD resolution, even with real-time lighting, shadows and reflections enabled.

We started to see the limitations of the CAD-focused GPU in game engine design viz application LumenRT, where frame rates dropped to 13.5 FPS with one dataset. This will only get slower at 4K resolutions, so those who take their real-time visualisation more seriously, or want to take their designs into VR, should consider a Quadro P4000 (which we also tested) or even a Quadro P5000, Quadro P6000 or AMD Radeon Pro WX 9100.

The APEXX S3 can actually accommodate up to three GPUs (two double slot, one single slot) thanks to its 650W PSU, so there are plenty of options for those using GPU renderers like V-Ray RT or Radeon ProRender.


Overall, the APEXX S3 is a very impressive high-performance CAD workstation built around a solid, well-engineered chassis. There is a downside, however. Quality like this comes at a premium and our review machine will set you back £2,899 (with a Quadro P2000) and £3,299 (with a Quadro P4000). This is notably more than a similarly specced machine from other custom workstation manufacturers in the UK. BOXX justifies this price tag not only by the quality of its machines but also the quality of its tech support, which in the past we have found very knowledgeable in a number of CAD and rendering applications. There are many BOXX customers who feel this is a price worth paying. BOXX Apexx S3 WS11

Price £2,899 - £3,299 (see text)


This article is part of an AEC Magazine workstation special report. To read articles and reviews in this report click on the links below.

Desktop Workstation Buyer’s Guide
Essential advice for those looking to buy a workstation for product development

Workstation Specialists WS-1160A
AMD CPU and AMD GPU combine for a powerful workstation for CAD,viz and VR

AMD Radeon Vega GPUs
What does AMD’s Vega GPU architecture bring to CAD, VR, viz and GPU rendering?

Armari Magnetar R80 (Pre Production Unit)
This dual Intel Xeon Gold workstation delivers the goods in single and multi-threaded workflows

Boston Venom EPYC (Pre Production Unit)
Dual 32 core AMD Epyc CPUs make this rendering beast fly, but it’s at the expense of single threaded performance

Mobile workstation buyer’s guide
A rundown of the things to look out when buying a professional 3D laptop

Wacom MobileStudio Pro 16
Wacom’s legendary pen technology is embedded in a pro 3D tablet

HP ZBook x2 G4 (Pre-Production Unit)
This detachable 2-in-1 combines Wacom pen technology with a Quadro GPU for 3D CAD

PNY PrevailPro P4000
This slimline 15-inch mobile workstation breaks all the rules by putting a powerful ‘VR Ready’ GPU at its heart

Dell Precision 7720
With powerful processors, impressive cooling, good serviceability and excellent build quality, this 17” mobile workstation is hard to beat

Choosing a workstation? It’s not that straightforward
How to future proof your workstation to support new and emerging product development workflows

Rendering beyond the CAD workstation
When rendering work is on the cards, what’s the best way for a firm to get its machines and its workflows up to speed?


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