Anyone that has troubleshooted problems with AMD/ATI graphics card crossfire configurations will probably know about Ultra Low Power State (ULPS). ULPS is a sleep state that lowers the frequencies and voltages of non-primary cards in an attempt to save power. The downside of ULPS is that is can cause performance loss and some crossfire instability.
ULPS is controlled via a registry value named "EnableULPS" located under the "HKLM\SYSTEM\CurrentControlSet\Control\Video" key, it can be disabled by setting the value to 0 or enabled with 1. As there are often multiple EnableULPS values in the registry for different cards and even older graphics cards that were previously in the system, it can be a tedious task to manually make the changes.
This is a simple tool written in the AutoIT scripting language, it searches the HKLM\System key and changes all EnableULPS to either 0/1 as defined by user input.
You can download the binary here (or source if you are interested) from my Github.