That's good to know. Both my G5s needed PRAM resets (Option-Command-P-R, which is quite special to manage with one hand), SMU resets (the tiny tact switch below the SIMMs) and a battery check. Just as well the older G5 didn't need a new PRAM battery: they use those infernal 1/2 AA 3.6 V cells that Macs since the Classic have used. Hard to find and expensive (Sayal has em for $10). 

Before all this, I got no display, no boot and cleared-for-takeoff fan noise. 

 Stewart