I recently obtained three power pc G5 Apple Macintosh desktop computers. The first one I diagnosed as not posting and booting properly. I noticed that the power button light would flash twice every five to ten seconds or so.
Also, I noticed that this Power PC G5 had only one memory module installed. This computer is compatible with older school DDR 184 pin modules. I am going to describe to you how to install RAM in iMac G5. You must install this memory in pairs.
There are a total of eight random access memory slots in this Power Macintosh computer. There are two sets of memory slots labeld 1-4. You must install at least two memory modules in order to get this machine to boot properly.
Also, you need to use the correct random access memory. PC3200 184 pin double data rate synchronous dynamic random access memory. Install one memory stick in each numbered one slot. You can install up to 8 gigabytes of total memory.
However, they must be in pairs and the same size. For example I installed two 512 Megabytes DDR SDRAM in this computer using both labeled slots 1. I powered on this computer and I heard the proverbial apple chime sound.
Also, I looked up the flash codes for this Power PC G5 Macinstoh and found out that when the power button flashes twice it is generally a random access memory problem. In order to open this system case there is a latch on the rear. You just pull the latch towards you and that releases the system cover.
You do NOT need to fuck with any screws with this older type of Power PC Macintosh computer. Also, the memory is located under neath two fans. The fans are removed by pulling up towards you on a plastic handle.
I was able to salvage this Apple A1047 EMC 2061 power personal computer.