How Would The New iMac Compare To My Old PPC G5 Power-Mac?

Question

I'm a bit out of the loop as far as the performance increases since I bought my G5 Power-Mac several years ago and if I'm honest, never really understood them that well anyways...
What I'm wondering is how the new iMac would compare to my old Power-Mac and would it be able to do what I need it to do. Here's what I have now (from my system profiler). A PowerMac PPC G5 (1.1) 2.3ghz Dual CPU. Bus speed 1.15ghz. It also has 4.5GB of Ram... I also have a dual monitor set-up but would obviously get rid of one if I bought the new iMac. The display I would be keeping would be my 30" cinema display. Would I be able to continue to use that monitor without too much hassle in a set-up with the iMac?
Any help, opinions or insights appreciated!

Answer 1

I have a 2.0 GHz dual core (PCIe slots) Power Mac G5 (the +late 2005+ model). It has 4GB RAM and the low-end 128mb NVIDIA GeForce 6600 LE. The max is 16GB.
I also have a 2.0 GHz Core 2 Duo 17-inch white iMac. It has 2GB RAM and ATI Radeon X1600 (128mb) for the built-in graphics. The max RAM is 3+ GB.
Both run Leopard. Both have two displays. I mostly use the iMac currently and another family member uses the Power Mac G5. These two configs feel about equal. Some apps seem to be better optimized for Intel these days. Other older apps are PowerPC-based apps, so the G5 runs those better without the need for Rosetta on Intel. In day-to-day use, I can't say that one is better than the other.
But that's with an older Intel iMac (the low end model even when it was new). For your comparison, the current high-end iMac will undoubtedly be faster. However, with both running Leopard, I don't think the new iMac will be a +quantum leap+ in better performance. Whether the actual difference is worthwhile to you will depend more on how you use your Mac. Once Snow Leopard comes out, with it's better optimization for Intel and more efficient use of multiple processors (and other technical improvements), the story may be different.
With the new iMac lineup, you can use a 30" Cinema display (as an extended desktop) with an adapter off the Mini DisplayPort. It says so on the specs page
http://www.apple.com/imac/specs.html
"Mini DisplayPort output port with support for DVI, VGA, and dual-link DVI via adapter."
"Simultaneously supports full native resolution on the built-in display and up to a 30-inch display (2560 by 1600 pixels) on an external display."