Heat: Adding additional drives internally to the PowerMac G5 using the G5 Drive Bracket did not noticeably cause the fans in the G5 to run more often, but I was able to record an increase in temperature of 4-5 degrees in the CPU A and B sensor readings using ThermographX. While I did not see a problem with running two additional drives from a temperature basis, I would install ThermographX and make sure temperatures stay within reasonable levels in the CPU areas, especially if I was running a three drive configuration.