TIMING: Running on a Windows 11 laptop may negatively impact timing [42409]

This article applies to:

E-Prime 3.0

E-Prime Go 1.0

NOTE: We have observed this issue when running experiments on battery power with a specific Power Mode on Windows 11. We have not observed this issue on Windows 10. However, we always encourage running on line power where possible (i.e., machine plugged in) regardless of the Windows version or Power Mode setting. Newer versions of E-Prime (3.0.3.219 and later) will produce a runtime Experiment Advisor Finding when an experiment is run on battery power. In addition, by default E-Prime (3.0.3.219 and later) logs a new variable to capture any impact on OnsetTime whenever the Time Audit OnsetDelay is logged for the E-Object (see INFO: OnsetAckDelay Logging in E-Prime [42766]).

Symptoms

An E-Object may encounter the following timing issues:

The OnsetTime reported may be inaccurate and therefore can impact the next target OnsetTime. As a result, when running with Event timing, display objects may remain on screen longer than the specified Duration, although the default setting for RefreshAlignment will help mitigate this issue.
The "task" component of a TaskEvent defined for the OnsetTime "event" may be delayed.
The RT and RTTime may be inaccurate because the Object's Input Mask is not armed during the delay period before the OnsetTime is set.

Detail

Windows 11 laptops may exhibit timing issues where the OnsetTime is delayed and the OnsetTime value is inaccurately assigned and logged. Typically, this issue only occurs while on battery power. This delay period typically lasts a few milliseconds, but can be greater than a refresh, and does not occur on every trial.

PST recommends running the battery test experiment attached to this article to test if:

the issues exist on your machine
and if so, whether the workarounds described below fix the issue

The test experiment should run in less than two minutes. A "Pass" or "Fail" message is displayed after the last trial. The data file (.edat3) can also be examined to confirm that the entries in the TestResult column are set to "Pass".

Workaround

The following workarounds are possible:

Workaround 1:

Plug the machine into line power and do not run on battery power.

Workaround 2:

Change the computer's Power Mode setting. We observed these issues when using "Balanced" or "Recommended" settings. To check this setting and change if needed, open the System Settings (i.e., press Windows key + I), select Power & battery, and change the setting from "Balanced" or "Recommended" to a "Performance" mode (the specific Performance setting name may vary with specific Windows versions).