Power Mac G4 (867) Upgrade - DP or SP? And more RAM?

Question

I only want to do this once, and would like to get it right first time.
Because price is an object. (I'd love to get a G5, but it's out of the question).
So if you can spare the time to offer some advise I'd be most grateful.
I have a PowerMac G4 867 (Quicksilver) with 1.12Gb SDRAM currently running OS 10.5.2.
(And it runs quiet well, but needs a little bit more "grunt").
Model Name: Power Mac G4
Model Identifier: PowerMac3,5
Processor Name: PowerPC G4 (2.1)
Processor Speed: 867 MHz
Number Of CPUs: 1
L2 Cache (per CPU): 256 KB
L3 Cache (per CPU): 2 MB
Memory: 1.12 GB
Bus Speed: 133 MHz
Boot ROM Version: 4.2.5f1
I'm considering either a:
*FastMac Motorola G4 7455 @ 1.53 Ghz Single Processor* (Model: APP-6216)
or a:
*FastMac Motorola G4 7455 @ 1.4 Ghz Dual Processor* (Model: APP-6280).
(I've checked and my 867 will accept a dual upgrade).
There's a price difference of US$150.00 or AUD$164.95 between the 2 options.
+The specs for the 1.53 says that it "Operates @1.5Ghz on a 100Mhz System Bus".+
+Would having a 133 Mhz Bus mean it operates better?+
As I understand it a dual processor is only really benefical if the software you're using is designed to take advantage of two processors, otherwise it just uses the one. So is there an advantage in a dual processor if you don't know wether the software you're using uses 2 processors? Is there a way to tell what software is dual compatiable?
As the price difference between the two options isn't too bad, (for me at this time at least), should I opt for the slightly faster single 1.53 or go for the dual 1.4? I know it's "one of those questions", where the answer depends on many factors, but generally speaking?
And after some research it appears the most RAM I get install in my dear old G4 867 is approx 1.5Gb. And updating one slot will give me that. Is it possible to add any more? Is there an expansion option that I'm not aware of?
That's it.
Positive feedback most welcome.
And *Many Thanks* in advance.

Answer 1

japamac wrote:
Hi-
Hello, and many thanks for taking the time to reply.
If you are going to use any photo, video, or audio editing software, get the dual processor upgrade. The OS also uses the dual processors. Any amount of multi-tasking will also benefit from multi processors.
Yes, I do a fair amount of photo, video and audio editing and rendering. Often I'll have more than one prgram running at once. eg: I'll have MPEG Streamclip converting an MPEG2 to a MOV file while editing in FCP or burning a DVD.
The RAM slots are as they are, and no mods are available. 1.5gb is max.
Such is life. Still I have "MenuMeters" installed, allowing me to monitor RAM usage, and I'm yet to see it all being used, even when the CPU usage goes to 100%. (Which is happening more often nowadays, thus the need for an upgrade.
If you are interested, for the same money as the dual, you can get a single 7448 based 2.0ghz processor upgrade. The duals will run about as fast as a single 1.8ghz, but the biggest advantage is to reduce the power demands and the heat produced. The 7455 processors, though very good, do produce more heat, and draw more power, than a 7447 or 7448 processor upgrade.
The other aspect of the 7448 that makes it attractive, is a 1mb L2 cache. Though no L3, the proximity of the large L2 cache makes for a faster processor than the 7447, or even 7455.
I was thinking it might be better to stay with the 7455, especially when going dual.
Does it matter if I change the model of the processor? I was under the impression is was better to stay with the original model type. eg 7455.
That said, the FastMac processors are good upgrades.
The 2Ghz is VERY tempting! But given that I'm doing more video and audio work, (at the same time), it seems the dual 1.4 is the better option. Or is it? Decisions, decisions.
Many Thanks. Jay.