Definition:
When multiple video cards are uncoordinatedly using the legacy VGA interface, one card might decode messages that were not sent to it.To solve this problem, it is needed an entity that controls all the accesses made using the legacy VGA interface. In Xorg this happens when multiple instances are running. It is important to note that some GPUs can skip completely if they are able to disable their VGA decoding resource.
Heart of The Ocean 