Can I use a B&W G3 Zif in a Biege G3?

I think all Mac ZIF's are basically interchangable. The multipliers would need to be reset... for example a 400 Mhz ZIF would run at 4X on a 100 Mhz bus... 6X on a 66 Mhz bus (396 Mhz).

yes, you can use a B&W ZIF in a beige, in fact, the machine I'm typing this on began life as a 233Mhz beige G3 Desktop then it was overclocked to 266Mhz, then I aquired a 300Mhz ZIF from a B&W and it was overclocked to 366, and is running stable and cool with the stock heatsink, you'll need to look up the jumper settings of course, but I can indeed say that it works.

beige G3's are often where original B&W cpu's end up after being upgraded. I have a B&W and when I bought a G4/500 zif for it I ended up selling the original G3/350 1mb cache to a guy that wanted to upgrade his G3/233. last I heard it was running well overclocked to 466.

Looks like several folks understand the process of installing an original B&W processor into a Beige G3.. I'd like to do this and need some help. I know how to install the processor itself. However, understanding and setting the jumpers correctly is another story. I HAVE set jumpers on the original Beige G3 to overclock it to 300mhz a long time ago. But to make it work with the B&W processor is another question...

Any clear advice would be greatly appreciated!

Many thanks.

Jason

Not ALL ZIFs are interchangable, many will run at 100MHZ OR 133MHZ, but not both. Early G3s and G4s can use the same CPUs, but once the 133MHZ bus G4s came out, that got broken. The Beige G3s are supposed to be 66MHZ, but there is usually a huge amount of leeway in clocking the busses of these machines. Up to the 80MHZ range should be no problem, probably not up to 100MHZ though.

When I was psyched to find a cheap G4 600 for my B&W, I put its G3 400 CPU into a Beige which I bought for $25. Runs great! There is a jumper block which one needs to tweak, it was easy enough to do by pulling the copper clips out with needlenose pliers, and putting them where I needed them. One can overclock the CPUs easily in the same process. I was conservative with the CPU for sake of stability, since this is a MIDI machine.

There is a CPU and bus jumper chart somewhere online, I think I found a link on lowendmac. Have fun!

Thanks for the input. I have found the CPU and bus jumper chart and for the life of me I cannot determine which settings to use, nor with trial and error get the machine to boot with the B&W G3 400 installed in the Beige. I'm stuck, and cannot find help with this.

I am assuming that the G3 400 will run OSX at least moderately well.

More specific advice on the procedures would be much appreciated.

Thanks.

Jason

set these jumpers, from the front of the mac - 3, 5, 6, 7

which will give you 400mhz at 66mHz bus. If this setting doesn't work, you've got other problems.

Here's a nice chart.

hth,

dan k

Exactly… what Dan K said, best to try with the basic configuration first. Less to troubleshoot that way. If you get it running how you like then, you can always try the other various settings.

My beige G3 400 handles Jaguar quite well, with a Rage128 video card (also from my B&W). Lots of RAM helps too. Any less than 128 MB would probably result in painful amounts of disk swapping, 512 MB recommended. Getting the CPU to run is not too much work, but getting OS X to install on an "Old World" machine can be tricky. I had to learn a bit of Open Firmware to install Jaguar on mine. Now it runs 10.2.8 and 9.2.2 really well!

M

Yes, I've even put a G4 ZIP in a beige G3.