diff --git a/contrib/thermald/surface_pro_5/README.md b/contrib/thermald/surface_pro_5/README.md
index 9e09f0589..2f2fa56b9 100644
--- a/contrib/thermald/surface_pro_5/README.md
+++ b/contrib/thermald/surface_pro_5/README.md
@@ -29,6 +29,8 @@ and cooling devices.
 - Various PCIe powersaving strategies
 - Intel p-state control for turbo-boost
 
+50-surface.conf contains sysctl tweaks advised by `powertop`.
+
 ## Installation
 
 - Make sure to install `surface-control`