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  • Answer

    It might be advisable to (de)activate the hardware acceleration.

    In RSTAB and RFEM, you can activate or deactivate the hardware acceleration (OpenGL) by using the menu 'Options' → 'Program Options' in the 'Graphics' dialog tab.
    In addition, an improved smoothing (antialiasing) can be set in the same dialog box to prevent the edge effect. Both options are only activated after restarting the program.

    It could also be a problem that the graphics card driver is outdated. Under certain circumstances, this may lead to problems when using RSTAB and RFEM. I would, therefore, ask you to update the driver.

  • Answer

    This problem is not caused by RSTAB or RFEM, but by the clipboard capacity of Word.
    When printing the graphics to the clipboard, a maximum resolution of 4000 x 4000 pixels is possible. The maximum image dimension (i.e. height or width) is governing and the smaller side dimension is scaled down.
    Thus, if there is a nearly square graphic that is then to be saved with the maximum resolution, the result is a file size of 4000 * 4000 * 3 = 48,000,000 bytes = 48 MB.
    Word usually can 'remember' up to 24 elements in the clipboard.
    Thus, the clipboard capacity of Word can be reached quickly and the other figures are no longer recorded.
    To be able to insert further graphics in Word, it should be stopped and restarted.

  • Answer

    Yes, it is possible.

    All images will be locked in the printout report when using the relevant button on the toolbar.

    Additionally, the option 'Block Graphic (Without Update)' can be selected when printing the graphic into the printout report.

    A graphic already contained in the printout report can also be locked retroactively. To do this, right-click the graphic and open the 'Properties ...' window. In the 'Graphic Printout' dialog box, there is an option 'Block Graphic (Without Update)' which can be selected.

    Locked graphics are indicated by a small lock symbol in the navigator of the printout report.

  • Answer

    3d objects in the format "3ds" can be easily loaded in the program via Insert -> visual objects in the existing model (see image). In the mask "new visual object" the scale, the insertion point and the rotation angle can be adjusted.

  • Answer

    If you want to print graphics in a report, the corresponding subitem must be active in the selection of the printout report in the "Global Selection" tab, see Figure 1. As a result, the tables are also displayed.

    If you only want to print pictures in the printout report, it is necessary to deactivate the tables in the tabs, see Figure 2.

    Afterwards, it is also possible to save report templates so that they can be used again in other positions. New templates can be defined in the printout report menu:
    Settings → Printout Report Template → New or New from Current Printout Report, Figure 3.

  • Answer

    ​In general, it is difficult to make a generalized statement regarding optimal hardware. It always depends on the models you wish to calculate. The following information may be useful for configuring a computer optimized for your purposes.


    Depending on the individual application, the system for RFEM can be optimized in two different ways:

    1. As many cores as possible.
    2. Fewer cores but the highest possible turbo boost.

    The first alternative is reasonable under the following conditions:

    - Large models with solids and / or many surface elements
    - Relatively few load cases
    - Extensive calculations with RF-STABILITY and RF-DYNAM-Pro

    The more CPU cores there are in a system, the greater the overhead for communication between them becomes. More than 10 cores are therefore not much of a performance increase. Hence, it makes little sense to use systems with several processor sockets.

    The second alternative is reasonable in the following use cases:

    - Member models
    - A lot of load cases
    - Extensive calculations with modules (except RF-STABILITY and RF-DYNAM-Pro)

    Which of the alternatives suits you better can be tested in the following manner: Start a typical calculation. Keep an eye on the processor load in the task manager. If it is at ~100% for processors without hyperthreading or at ~50% for processors without hyperthreading, choose alternative 1.

    If the processor load is at least at 25% (processors without HT) or 12.5 (processors with HT), alternative 2 is the more suitable one.
    For alternative 1, we recommend one of the following processors:

    - Intel® Core™ i7-8700K
    - Intel® Core™ i9-8950HK
    - Intel® Core™ i9-7900X
    - Intel® Core™ i7-7820X

    For alternative 2, we recommend one of the following processors:

    - Intel® Core™ i7-8700K
    - Intel® Core™ i9-8950HK
    - Intel® Core™ i7-8086K
    - Intel® Core™ i5-8600K
    - Intel® Core™ i7-7740X

    RFEM does not benefit from hyperthreading. There are therefore no disadvantages to not having a processor with hyperthreading.

    RSTAB can only use one processor core. If a computer is to be used only for RSTAB, equipping it according to alternative 2 makes sense.
    Generally, Intel processors are recommended. We do not recommend using AMD processors, but have no experience or feedback regarding Ryzen processors.

    Modern processors have sophisticated temperature management. Depending on the processor temperature, the clock speed is adjusted dynamically, which means that good cooling can increase a processor's performance. We therefore recommend a generously sized computer case and a good cooling fan for the processor.

    XEON processors do not have any significant advantages in regards to the computing speed. In these processors, the same cores as in the Core i processors are used. The additional functions these processors provide do not lead to a performance increase in RSTAB and RFEM.


    A quick RAM connection is important for the speed, especially for RSTAB. For that reason, DDR4 RAM should generally be used.
    The optimal RAM size depends on the FE mesh of the model. Unfortunately, the size of the required memory cannot directly be inferred from the number of FE nodes. Testing it is the only way.

    For that, use a model from your practical work that is as large as possible. Select the direct solver (see Figure 1).

    Keep an eye on the utilization of the working memory in the task manager. If it approaches 100%, your computer does not have enough RAM.

    If the RAM size is sufficient for the calculation, adding more memory will not result in increased speed.

    Sometimes it makes sense to perform comparative calculations of different variants parallelly in several instances of RFEM. For example, if you wish to run 2 parallel instances of RFEM, the required working memory doubles.

    Equipping the mainboard with RAM in such a way that it is easily upgradable is sensible.

    ECC memory, as it is offered in some workstations, has no practical use for RFEM in terms of speed.

    Graphics card

    For the video card, we recommend a graphics chip from Nvidia. The integrated graphics processors from Intel are unsuitable.

    We do not recommend the expensive Quadro cards and instead recommend a "gaming card" of the GTX series with Pascal architecture (GTX 10XX). In terms of hardware, GTX and Quadro cards differ only slightly. The drivers for the GTX cards are usually less of a problem with regards to RSTAB / RFEM and the GTX cards are less expensive than the Quadro cards.

    The size of the video memory of the card is irrelevant for RSTAB / RFEM.

    What is important is that the latest driver for the graphics card is installed.


    Regarding computing speed, the use of an SSD instead of an HDD is advantageous only in exceptional cases. They do have an advantage when it comes to saving or reading large RFEM files, though.


    The software that is running in the background may be pivotal for the calculation speed.

    Antivirus software running in the background may significantly slow calculation. During calculation, RFEM has to write many files into the work folder and read from it again. It could have a positive impact on the computing speed to remove this folder from the real-time monitoring of your antivirus software (see Figure 2).

  • Answer

    Yes, it is possible. For this, right-click the picture and select "Edit". The main program appears where you can change views and display or hide model data, for example. Modifications are trasferred to the printout report directly.

    If you want to change the size of member diagrams or adjust deformations, select "Properties" and click the "Factors" tab in the following dialog box where you can also find other options for the graphic adjustment.

    The size of load figures or fonts can be adjusted in the display properties. However, these settings are global for all graphics.

  • Answer

    Unfortunately, the answer is no. In our experience, however, the quality of the printout mainly depends on the print driver. Please try to find the solution here first if you encounter printing issues.

    If the rendering is displayed in a jagged way in RSTAB or RFEM already, this is due to the graphics card. The rendering uses the OpenGL functions. You can control them after selecting on the menu "Options" -> "Program Options," and going to the tab "Graphics" (see figure). Another solution for improving the display might be to use a different graphics driver.

    During plotting, a large amount of data is processed. Sometimes, the limits of the operating system are reached. The plotting output in the size ISO A0 with a very high quality might therefore become problematic. RFEM does not use its own drivers to control the plotter but the drivers included in Windows. Tests have shown that these drivers are instable and defective. Therefore, it is highly recommended to use the original drivers of the plotter manufacturer. The plotter should not be set as the default printer in Windows but chosen when printing.

    Many plotter drivers offer alternatives to prepare the graphic in the plotter or in the computer. It is faster in the plotter, but because the plotter has only a very small random access memory, parts of the picture might be lost. This results in missing descriptions, lines, or fillings. Often, the plotter also shows a corresponding message, for example HP "Out of Memory, Data was lost."

  • Answer

    You can rotate graphics by 90° by using the properties in the graphics.

    To do this, right-click the graphic in the report, and select "Properties" on the context menu.

    In the "Properties" tab, you can specify the angle for the rotation (see figure).

  • Answer

    Unfortunately, the graphics cannot be written directly in a file of the JPG or BMP format. With the print option using the clipboard you can insert graphics into other programs that allow for editing and saving BMP or PNG files. A changed background color, however, won't be transferred.

    Among its Accessories Windows 7 offers the "Snipping Tool" which is a screen printing program that you can use to create graphics of the file formats GIF, PNG and JPG.

    In addition, there are also professional programs like Snagit®. When you insert graphics for example in PowerPoint, we recommend not to change the size by pulling the edges as otherwise the representation becomes pixelated. If you want to have it in another size, you can adjust it in the image editor (pixel setting etc.), or you can print the picture again but with another view.

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