Here is my take which can be digested at will.
At this point it would not be much of a performance inprovement to increase the FSB speed. This would especially be the case at the odd frequencies mentioned. Running 1 to 1 may offer marginal improvements but there are far to many other bottle necks to contend with.
Probally the two most important things that could be done to improve performance at this point is to implement an integrated memory controller and to increase the cache size.
A larger cache size and other immprovements there, are absolutely required; it does make one wonder about the 970FX and why Apple & IBM did nothing more than a die shrink. The problem is that memory is not getting faster at a rate that really matters, this has a significant impact as clock rates increase. This requires proportionally larger caches as clock rates increase to maintain good performance. At this point though the modest increase from 2 to 2.5 GHz does not seem to have had a major impact on scaling with the few bits of performance information seen so far.
As far as people loving an increase in bandwidth, that is only of importance if the rest of the system can make use of that bandwidth. To that end the current G5's are a rather poor example of computer technology actually making use of the bandwidth available. Even if the next generation G5 went with PCI-Express video and a raid controller for disk I/O there is still an issue of actually making use of that bandwidth. Memory is the modern choke point and everything data wise eventually goes there.
It should be noted that one very promising new technology from Apple is the use of the GPU. This has the potential to reduce demand on main memory, thus freeing up bandwidth to this overloaded subsystem. Of course this then loads another subsystem. The point is that there is no free lunch, any increase in bandwidth has to be followed by other improvement to be worthwhile. Bandwidth in and of itself is not a feature, even though Apple may be marketing it that way. All the bandwidth in the world will not make up for slow components else where.
Originally posted by Altivec_2.0
The next revision of PowerMac's may not have a faster processor, but what it Apple kept working on improving all the smaller stuff. The FSB which is at 1.25Ghz, if they boost it to 1.75Ghz, performance would be increased no matter how fast the processor is? correct? If Apple could get there FSB to 2Ghz, that would be quite impressive. If they implemented faster ram (they have 550Mhz ram out PC4400), unidirectional traffic between I/0 and system controller, unidiretional PCIe x16 slot.
If Apple Increased all this other stuff besides the processor, they would be setting up a rock solid, powerful base when we get that extra 1Ghz boost from a dual 3Ghz system. The new 3Ghz chips would absolutly love all that bandwidth. 16GB's of aggregate FSB bandwidth is incredible and all creative pros would love it.
The 2.5Ghz G5 chip is powerful enough for now IMO, we could get dual 3Ghz performace if the ram was upgraded to 550Mhz, and FSB at 2Ghz.