Hardware

Below are some general questions about our hardware. For device-specific questions, please see our relevant subpages:

What are the system requirements for VPixx hardware?

The short answer: our hardware is compatible with all recent major operating systems. To see what versions of each operating system we currently support, see Software Download .

The long answer: it depends on what you are trying to do. While our hardware supports all major operating systems, some of them are better suited to research. On the one hand, for timing-sensitive experiments and low-level control, open-source advocates like the makers of Psychtoolbox strongly recommend Linux-based operating systems. On the other hand, some major high-level experiment software tools like Presentation and E-Prime are only supported on Windows. 

If you need an out-of-the box solution that works, the dual boot Linux/Windows machine service is thoroughly tested and tweaked. It is the only complete system guaranteed to work with our devices and is backed by a 3-year manufacturer’s warranty.

What kind of graphics card do I need?

We have a whole page dedicated to this.

What is the difference between a “Lite” and a “Full” data acquisition system?

As of September 2023, all units sold by VPixx Technologies are equipped with the “Full” data acquisition system. If you would like to upgrade a legacy Lite system, please contact sales@vpixx.com with your product serial code for pricing and details.

Can I upgrade my “Lite” data acquisition system to a “Full” system?

As of September 2023, all units sold by VPixx Technologies are equipped with the “Full” data acquisition system. If you would like to upgrade a legacy Lite system, please contact sales@vpixx.com with your product serial code for pricing and details.

Can I drive VPixx hardware from multiple PCs?

Yes, you can. The easiest way to do this is to use a KVM switch. These switches allow you to toggle between different PC inputs to the same display hardware. We recommend the following models:

Can I use a video adapter if my graphics card does not have dual-link DVI output?

Our VIEWPixx CRT replacement monitors use Dual-link DVI, and now come with a DisplayPort to Dual-Link DVI adapter. Our other systems use DisplayPort. Below are some general recommendations for older systems and systems without our adapter.

Can I use multiple screens at the same time?

Best practice during data collection is to disable all secondary displays and only run the stimulus display. This reduces load on your graphics card and minimizes the risk of frame dropping and other latency issues associated with overtaxing your graphics processor.

Of course, in some labs this impossible, or at least very inconvenient. Your main display may be in another room, or you may be required to monitor specific trial metadata in an experimenter view. 

There are two general solutions for running multiple displays during an experiment. First, you can connect a monitor to the secondary video port on the side of your VPixx device (available on all screens and I/O hubs except for the VIEWPixx /EEG). The hardware will generate a copy of the experiment display and show it on this secondary “console” display. You can then use the console to keep track of participant progress.

Because the console duplicates the video to the main display, it does not add any load to your graphics card; however, by default it can only mirror the main display. Some of our special video modes such as M16 allow for an overlay on the console, which allows you to show some trial metadata specifically in the experimenter view. The console output for the TRACKPixx3 2 kHz eye tracker can also show a live camera feed, in addition to the participant’s view. 

Please note that not all monitors will work well as a console display. We maintain a list of third party screens we have tested and verified work well with our devices. For an up-to-date list, please contact scientist@vpixx.com.

The second option for driving a secondary display is to drive it directly from a second port on the graphics card. The effect this will have on the performance of the main display will vary from system to system. A powerful graphics card may be able to manage both displays without significant frame dropping. If you decide on this route, it is a VERY good idea to run some synchronization tests prior to data collection, to ensure you have a tolerable rate of frame dropping and you are not compromising your stimulus presentation.

I need to connect my VPixx hardware to another system via the I/O ports. Where do I start?

This response is focused on setting up hardware. For tips on how to set up triggers in software, please see our software demos. Pin assignment information can be found in your device user manual.

VPixx hardware has several ports dedicated to input and output. Each port consists of a series of pins that are numbered according to an industry standard. Our I/O ports use a DB-25 connector, and so have 25 pins labelled 0-24.

Other common I/O port formats include BNC/coaxial (common in MRI/MEG systems) and other multi-pin D-sub connectors like DE-9. It is possible to have a cable with different types of connectors on each end, or a cable with one end that splits into multiple connectors or even exposed wires that can be slotted into other electronics.

In all cases, each pin on an I/O device has a specific role, or assignment. Pin assignments vary from system to system. Pin 1 on system “A” might listen for incoming digital signals, while pin 1 on system “B” acts as a ground. 

In order to connect two I/O devices, you must know the specific pin assignments of both ends, and make sure your cable is wired to connect the appropriate pins to one another. Do not assume any cable with the correct number of pins is wired to work with your particular configuration. Connecting pins with incompatible assignments can do physical damage to your ports.

Pin assignment details for specific ports are typically provided by the manufacturer. Pin assignments for all VPixx I/O ports are listed in the specific device user manual. The exception to this is a PC Parallel Port, which has a specific industry standard pin assignment.

Our team is familiar with many neuroimaging, eye tracking, and neurophysiological solutions and can provide advice on how best to connect hardware based on your specific synchronization needs. We manufacture a variety of trigger cables, custom cables and adapters in order to connect different systems safely. If you’re not sure how best to configure your system, we are happy to help.

For more details, please contact our team of trained vision scientists at scientist@vpixx.com. 

How do I (re)calibrate my display? How often should I recalibrate?

Instructions for running our automated calibration routines for the VIEWPixx and VIEWPixx /3D CRT replacement monitors, and the PROPixx DLP projector, can be found on page 115 of our Product Application Guide [pdf].

Please note that the automated calibration routines available in our vputil and PyPixx utilities are designed to work with the specific versions of the X-Rite i1 Pro and i1Display Pro sold by VPixx. These tools have custom software designed to work with our devices. An X-Rite device purchased from a third party vendor, or from X-Rite directly, will NOT work with our calibration routines. The VPixx versions of these tools will not support X-Rite’s own calibration and measurement software.

Our displays use LED light sources that have a very long lifespan. They are are factory calibrated prior to shipment according to the following specifications:

• VIEWPixx /EEG

  • Luminance with scanning backlight: 100 cd/m^2

  • Luminance without scanning backlight: 250 cd/m^2

• VIEWPixx /3D

  • Luminance with scanning backlight: 100 cd/m^2

  • Luminance without scanning backlight: 250 cd/m^2

  • White point: D65

• VIEWPixx:

  • Luminance with scanning backlight: 100 cd/m^2

  • Luminance without scanning backlight: 250 cd/m^2

  • White point: D65

• PROPixx:

  • Luminance: Depends on projection screen size, type  and distance

  • White point: D65

We have found that our displays maintain luminance and chromaticity characteristics consistently for a long time. Your displays should not require re-calibration for about 5-10 years, depending on how heavily they are used. After 5 years you may wish to take occasional measurements to verify your displays are still within an acceptable range of luminance/white point.  

Is VPixx hardware rated for medical applications?

VPixx Technologies develops and manufactures research tools, which are not regulated for use as diagnostic or medical equipment. 

To be rated as a medical diagnostic device, research equipment must go through comprehensive regulatory testing specific to each country (e.g., FDA, MHRA). This certification process takes many years, and may or may not be recognized by other countries and governing bodies.

VPixx Technologies’ goal has always been to enable researchers to push the boundaries of what can be studied in vision research. Our products and tools are often developed by request, and in response to specific, pressing research questions. We have chosen to dedicate our efforts to this fast-paced development, rather than attempting to acquire medical ratings for our devices. 

How do I clean my VPixx devices and displays?

Cleaning recommendations for specific devices can be found in the documentation for that device