TIMING: How do I set a specific refresh rate for older Windows operating systems using E-Prime 1.x? [17198]

This article applies to:
E-Prime 1.x

Detail
The ability to set an experiment's refresh rate varies depending on the operating system, display adapter, and monitor. Some refresh rate and resolution combinations are not possible depending on these factors.

Windows 95, 98, 98 SE, and ME

On the earlier Windows Operating systems mentioned above, if the experiment's settings for resolution and color depth are the same as the experiments, then the display device will use those settings.

If the desktop and the experiment are both 640x480 16-Bit, then the display device will use the refresh rate of the desktop settings because it does not have to switch display modes.
Therefore, to set a specific refresh rate on earlier Windows Operating Systems, match the desktop and experiments settings to the desired design.

If the desktop and the experiment differ in any manner (xres, yres, or color depth), then the display device will be required to change the display mode on the system. When doing so, the display device will attempt to use the optimal (highest) refresh rate it determines both the display adapter and monitor can handle. This provides for the quickest screen refresh possible, but does not guarantee what the experiment is designed for or consistency between lab machines.

NOTE: The refresh rate override through DXDiag or the DirectX control panel applet outlined for Windows 2000/XP machines has been found to not work on the majority of earlier Windows Operating systems. To set the experiment to a specific refresh rate, you must match the desktop settings.

Windows 2000 and XP
On Windows 2000/XP systems, the experiment will always use the display adapter's "default" refresh rate, which is typically 60hz. Unlike Windows 9x machines, the "default" refresh rate is used even if the experiment and desktop settings match.

Windows 2000/XP provides the ability to override this functionality. To override the "default" refresh rate, choose one of the following options:

Option 1 - DirectX Control Panel applet

1. Open Control Panel
2. Open the DirectX applet
3. Select the DirectDraw property page tab
4. Change the "Forced Refresh Rate" dropdown to the desired value
5. Click OK and close open windows.

Option 2 - DirectX Diagnostics

1. From the Start Menu, select Run
2. Type in "DXDiag" (w/o quotes) and click OK
3. Select the More Help property page tab
4. Click the "Override" button
5. Type in the desired value into the override edit box.
6. Click OK and close open windows.

NOTE: Changing the DirectX refresh rate override value will affect all applications that use DirectX.

 
WARNING: Setting the display adapter to a refresh rate the monitor cannot handle may cause damage to the system. Use caution when setting the refresh rate manually.

Windows XP with Service Pack 1

With Service Pack 1 for Windows XP installed, the above applies for if you use the DXDIAG override value. If you do not use the override value, then XP will use the current desktop refresh rate, no matter what mode you go into.