We'll definately have faster Minimum bus speeds in the next revision of the G4. Motorola introduced the PPC 7455 G4 with a 133Mhz bus, that's now changed to 150/167Mhz.
The PPC7457 is going to have a 200Mhz bus so that pushes up the bandwidth aswell. I'm sure apple will be using at least PC2700 RAM on all models and with the PPC7457 having twice the L2 cache and a 200Mhz FSB, I'd expect a 1.4Ghz G4 based on one of those chips to outperform the current 1.25Ghz G4 by more than the 12% you'd get from the increase in clockspeed.
If this means we'll have a line up like this :
dual 1 Ghz G4, 256K L2, 1Mb L3, 167Mhz FSB, 333Mhz motherboard.
dual 1.2 Ghz G4, 512K L2, 1Mb L3, 200Mhz FSB, 333Mhz motherboard.
dual 1.4 Ghz G4, 512K L2, 2Mb L3, 200Mhz FSB, 333Mhz motherboard.
then apple will have some decent models with reasonable bandwidth at last. Assuming the prices are the same as now.
Of course this line up would be better :
dual 1 Ghz G4, 512K L2, 1Mb L3, 200Mhz FSB, 333Mhz motherboard.
dual 1.3 Ghz G4, 512K L2, 1Mb L3, 200Mhz FSB, 333Mhz motherboard.
dual 1.6 Ghz G4, 512K L2, 2Mb L3, 200Mhz FSB, 333Mhz motherboard.
These could be the first macs that are pushing close to the throughput of 266MHz DDR without even having a DDR compatable chip.
I'm sure the difference between 1.6Gb/s and 2.1Gb/s is hardly going to cause a performance decrease of more than a few insignificant % anyway.
I know this is all rumour and nothing to get excited about but the prospect of faster cpus with faster throughput is good for everybody no matter what they like to do with their macs.
