Yet more README faqs.

README

@@ -1024,6 +1024,11 @@ I start it remotely?
 A: With linux, make sure to export the DISPLAY variable. On windows, you
 cannot access these monitoring values via a remote session.
 
+Q: I change my GPU engine/memory/voltage and cgminer reports back no change?
+A: Cgminer asks the GPU using the ATI Display Library to change settings, but
+the driver and hardware are free to do what it wants with that query, including
+ignoring it. Some GPUs are locked with one or more of those properties as well.
+
 Q: I switch users on windows and my mining stops working?
 A: That's correct, it does. It's a permissions issue that there is no known
 fix for.