Is there any such thing in a G5? Is there any hard limit, or formula for a limit, for how much RAM ArchiCAD can actually use (like: # Gb x processors, whatever)?
I overheard some IT guys saying that past a certain point ArchiCAD cannot profit from additional memory. Which I find hard to believe.
While others may actually know an answer based in addressability limits or whatever, my experience with a 2x2.0 G5 having 3.5 Gb RAM is that even when processing the largest and most complex of renderings that the Activity Monitor never showed Archicad asking for more than 1.9 Gb with plenty of remaining RAM available.
If you want to make Archicad work better, after you max the RAM, get a skookum graphics card - like 512 Mb. Someone posted here that they had several graphics cards working together and they could move large models around in OpenGL smoothly and quickly.
This is why Dwight experiences what he does. It didn't occur to me while I was writing but I wonder if the SSD's use the same SATA and can be installed in a G5 as a boot disk.
And a side note to Dwight's afterthought about a new graphics card is that Quartz Extreme is required and Core Image is a must if rendering is your goal.