Hello, My Powermac G5 refuse to start normally: sometimes, it boots perfectly, sometimes it doesn't. Switch on the G5: fans spin, no chimes, no keyboard, no video, fans accelerate few minutes after...I can just push the power button to switch off the G5. So, I clean up the G5, disconnected firewire matérials, ram, replace it, disconnected video card, hardrives, I bought new pram battery. Nothing changes. But, when it starts, the Mac is fully fonctionnal... Please someone help me ?