diff --git a/RELEASE_NOTES.rst b/RELEASE_NOTES.rst
index 6dc247b04..a1c807008 100644
--- a/RELEASE_NOTES.rst
+++ b/RELEASE_NOTES.rst
@@ -30,6 +30,7 @@ Highlights:
   repository when building the list of experiments.
 * The configuration entry ``rtio_clock`` supports multiple clocking settings, deprecating the usage
   of compile-time options.
+* DRTIO: added support for 100MHz clock.
 
 Breaking changes: