Project FrankenMac

[job]

I may be able to pick up an older Sawtooth tower in the immediate future (end of July).

I am planning on maxing this thing out as I don't have enough money to spend on a brand new Mac (i.e. G5). My estimated operating budget for the project is $300~500 for the actual tower/case/original CPU and around $300 for the CPU upgrade. I plan on salvaging my current Pro Apple Keyboard and optical mouse along with the 512MB PC100 RAM currently in my iMac and my Altec Lansing 2100 speaker set.

Before I go ahead and buy the Sawtooth tower I have a few questions:

1. I am looking at the CPU upgrades from Giga Designs. They have several different versions of the 800Mhz and 1Ghz G4 chip. What is the difference between the 1Ghz with the DDR L3 cache and the 1Ghz upgrade with the Synchronous Pipeline Burst (SPB) L3 cache. Both are running at the same speed (250Mhz - 1/4 the CPU speed.) Will I see any noticable speed improvements if I opt for the DDR version?

2. Can I safely overclock aforementioned CPU upgrades via the jumpers as listed on the Giga Designs website? I'm not going to try anything crazy here. I'd like to try running at 1.2 Ghz though, maybe 1.3Ghz as the Apple System Profiler apparently doesn't recognize a 1.2Ghz chip on a 100Mhz bus.

3. What type of hard drives can I put in this thing? Normal plain vanilla IDE drives? Or are these ATA drives? Is there even a difference?

 

[Eniregnat]

This is a project if you have time on your hands.
I would look for a used g4 tower if I really wanted performance at a price break. It's expensive, no matter how you do it.

In reverse order->
I think that the drives are IDE, not ATA. You may not be able to have slave drives with some of the older G3's. Somewhere I remember that an upgrade was needed to do that.

Overclocking->
If people have done it, it's probably safe. Remember, if they could of sold it for more money as a faster chip, they would of. Heat and burn out are issues, but hey, were chopping computers here. (In my experience the performance gain is little and the annoyance or processor glitches and possible data loss don't make it worth the effort.)

DDR is much faster and more expensive. Write them to see what the differences are. Sonnett Tech also makes upgrades. I don't have a link for them

This is the best I can do with my limited knowledge. I hope it helps, or at least spurs somebody to give better info.

 

[WannabeSQ]

As for the upgrade cards, xlr8yourmac has extensive reviews of many (all?) the G4 upgrade cards. And IIRC there was little difference between the DDR and the SDR L3 cache models, just cost. OWC also has an upgrade comparison page, with many benchmarks. There are more manufacturers than you mentioned, there are Sonnet, Powerlogix, Giga Designs, and OWC. The Giga and OWC ones are the only ones that have jumpers, which allow for overclocking, which BTW doesn't void the warranty. The Giga cards have jumpers for the core voltage, but that does void the warranty. Both Giga and OWC have up to 1.4ghz. MacBidouille did a test with the 800mhz model with no cache and water cooling and got 1.1ghz. MacB Overclocking I believe they were also going to overclock the 1.4ghz model with the same overclocking, they got 1.5ghz with air cooling, and hope for 1.6ghz.

 

[jamall]

Upgrading a G4

I asked the same question of the Gigadesigns support staff - reply: "To the best of my knowledge, our distributor partners do not have any
GC5-1000-D2 boards remaining in inventory...The difference in performance
between the SPB and DDR caches is about 4-6%. Due to the much higher
price (2x) of the DDR devices, we use them only on our highest
performing boards. For our value and mid range products, we use the SPB
devices."
In looking for a second hand Mac, the 133MHz bus models are worth the extra $50-$100 you'll pay. The extra 33MHz will give your processor upgrade that much more bandwidth to work with. The best value models to look at are the 466MHz and 533MHz digital audio G4s - don't worry about dual processor models if you're going to upgrade it anyway. The drawback of the 133MHz bus is that your PC100 RAM won't work, but RAM is so cheap these days (~$40 for 512Mb).
Check out Other World Computing's upgrades page for comparisons of the various upgrades running on different bus speeds.