Performance Difference Between Dual 2.7 and Quad, and Logic Pro

Question

I used to have a G5 DP 2.7 before it went bad and Apple offered me a Quad in exchange. I'd like to understand some details of the specs between these two computers and how they might translate with respect to running Logic Pro (which I'll get to in a minute)...
Listed below are the specs which I believe illustrate the significant differences between these two machines (this info is based on info gleaned from Macworld, since the specific specs of the DP 2.7 no longer appear on Apple's website):
Dual 2.7
(2x) 2.7 GHz, cache = 512K per processor, frontside bus speed = 1.35 GHz per processor
Quad
(4x) 2.5 GHz, cache = 2MB on-chip L2 per chip, frontside bus speed = 1.25 GHz per processor
So here's the link with Logic: it's become apparent of late that Logic Pro is not able to fully utilize the processing power of all 4 cores in the Quad. Reports are that performance tops out at 50% per processor, resulting in approx. 200% possible processing usage from the 4 cores in the Quad.
However, such a limitation in processor usage wasn't present in the DP 2.7.
So based on the information I've learned so far, it seems that the Quad and the DP 2.7 are almost equivalent in terms of processing power when running Logic Pro. Now, this is what I'm surmising, but, is this actually the case? At the end of the day, I'd like to know if the Quad indeed a more powerful computer than the DP 2.7 when running Logic Pro, or, did my exchange of DP 2.7 for the Quad constitute a "downgrade" of any proportion?

Answer 1

The only logical answer to Why Intels do and PPC don't is:
Apple want everybody to transition to their Intel boxes. The only way to do this is offer better performance in software tweaks for one system over the another, which begs the question what else will Apple do to software for PPC owners?
Having bought a Mac Pro, primerily for testing out certain software apz under Rosetta, I did a real time test between my 8GB RAM G5 Quad and my stock Mac Pro upgraded to 2GB RAM, batch processing 204 Canon 1DsMKII RAW files into 16-Bitt TIFFs. I put a thread on the Mac Pro forum here:
http://discussions.apple.com/thread.jspa?threadID=627916&tstart=15
I so wanted my Quad to squash the Intel invaded Mac, but results speak for themselves. The Mac Pro flattened the G5 Quad by over 23 minutes (it worked out as 1.7 times faster than the G5Quad).
If that's how it performs with 2GB RAM it's gonna really fly when I max it out. So, for musicians, I would imagine with the Quad core support for Intel Macs in Logic 7.2.2 makes a fairly straight forward decision. . .buy a Mac Pro and sell your PowerMac. More time composing less time waiting for renders (never used music software so if it doesn't render your composition place whatever it does do into the 'renders' slot )
P.S I hated, really hated having to say the Mac Pro toasted my G5 Quad, I so wanted the Intel to fall flat on it's aluminium as$, but it didn't. It's a quick machine. A very quick machine which toasted my Quad in real time tests using a universal Pro app from a 3rd Party (who would have no incentive to dumb down the PPC version as they sell their product to Windows, PPC OS X and Intel OS X)