diff --git a/FAQ.md b/FAQ.md
index 3b637ad..4c943ca 100644
--- a/FAQ.md
+++ b/FAQ.md
@@ -51,6 +51,9 @@ I don't really know.
 My theory, which is backed by exactly zero research and experiments, is that since SMT increases performance of a single core by less than 100% (usually it's closer to 30-50%), that 150% performance gets split between two threads, effectively reducing each thread's performance to 75% when both threads are under heavy load.
 It would then follow that disabling one of those threads would restore the remaining thread to 100% performance.
 
+# How does the charge limit work?
+Badly. It roughly mimics the default behaviour of charging up to 100%, then doing power passthrough until 90%. The upper and lower limits are obviously different, but that 10% window is maintained. The PowerTools has an important limitation over the Steam Deck firmware version, though: it only works while the screen is on.
+
 # TLA (Three Letter Acronyms)
 ## AMD
 Advanced Micro Devices: the company that makes the processor in the Steam Deck