The invention concerns novel substituted 6-benzyl-4-oxopyrimidines and pharmaceutically acceptable salts thereof. This surgical system comprises a medical impacting device that mates with a surgical tool such that the impacting device can be manually reciprocated along an axis of the tool to forcefully impact the impacting device on a portion of the tool. The method also includes providing power to the server arrangement using the first power supply and not the second power supply when it is determined that the power load requirement is below the threshold, and providing the power to the server arrangement using the first power supply and the second power supply when it is determined that the power load requirement is not below the threshold.