The System Options in Blender’s User Preferences

By Jason van Gumster

Whereas the Interface options dictate how you interact with Blender, the options in the System section, shown here, tend to dictate more how Blender interacts with you. Many options here are geared toward optimizing for performance, and generally the defaults work well.

The System options in User Preferences.
The System options in User Preferences.

Some of the more interesting options follow:

  • Compute Device: If you’re using Cycles as your renderer, the settings here are pretty important. If your computer has a sufficiently powerful graphics processing unit (GPU) — usually this is your computer’s video card — Cycles can take advantage of that additional processing power, dramatically reducing the amount of time required for rendering. Depending on your GPU type, you’ll want to set this to either

    • CUDA (for NVIDIA GPUs)

    • OpenCL (for AMD/ATI GPUs)

    You can then choose the specific GPU from the drop-down menu.

    If you don’t have the kind of GPU that Cycles can take advantage of, there’s no need to worry. The Compute Device defaults to None and Cycles will just use your CPU.

    As of this writing, the OpenCL option for Compute Device doesn’t work particularly well on AMD GPUs. There’s hope that it may be fixed and working in the future, but that depends on AMD changing their drivers. In the meantime, if you have an AMD video card, you’re probably best keeping the Compute Device option set to None.

  • OpenGL: If Blender is working sluggishly or if the interface looks really odd (noise, strange tears, repeating patterns), these settings are the first place to look to see whether you can get Blender working nicely. In particular, you may want to try enabling vertex buffer objects (VBOs). With VBOs enabled, Blender’s interface should be snappier on more modern video cards. However, on older hardware, VBOs may cause Blender’s screen to behave strangely.

  • Window Draw Method: This drop-down menu is another fine place to look if Blender is displaying bizarrely on you. The default setting of Automatic should give you the best performance on your computer. However, if you’re on an older machine, try seeing whether the Overlap or Full methods work better.

  • Region Overlap: If you enable this check box and you have a sufficiently modern video card, the regions in the 3D View (the Properties region and the Tool Shelf) will be semi-transparent, allowing your 3D scene to show through them. Not only is this attractive, but it helps keep as much of your 3D scene visible as possible.

  • Solid OpenGL Lights: With these settings, you can adjust the standard lighting used in your 3D View. Some Blender users set these colors to drastically different settings so that they can have a good sense of each side of their model and more easily see some of the contours. You have the ability to enable up to three lights. On each one, you can adjust the direction of the light by adjusting the X, Y, and Z direction values. You can adjust either of the two colors for the light (main color and highlight or specularity color, respectively) by left-clicking them and using the color picker that pops up.

  • Color Picker Type: Speaking of color pickers, Blender gives you the option of a variety of ways to choose colors while working. The default is a circular hue, saturation, value (HSV) color picker. It’s generally faster to use for choosing colors when painting. However, everyone has different tastes in what color pickers they prefer to use, and some color pickers are better than others for specific purposes. For that reason, a drop-down menu contains a selection of different color pickers that you can use in Blender. Play with the color pickers on the Solid OpenGL Lights and see which one suits you the best.