Hey all,

As some of you probably know, I recently bought a G3 PowerMac B+W. It's not bad, but I'd like a bit more speed.

Am I right in saying a G4 or G5 processor will fit right in and work? Also, will they be expensive, and where can I get them from?

Thanks a lot, as you can tell I'm a nub to Macs.

Fleabay seems to have G5 CPUs and logic boards going. I have no idea what a logic board is, but I'm assuming it's the mobo? Surely you could just chuck that in your G3 case and it would effectively be a G5...

Short answer is no.

There are big differences between the pin-outs for a G4 and a G5 compared to a G3. It's not a simple 'unplug CPU, plug in new one'.
There's usually a firmware upgrade involved as well, and I'm not sure how well the later versions of OS X play with the upgrades, really.

If you want to do a processor swap, prepare to spend about £300 on the new chip.
At which point, I'd show you the education site on the Apple Store, and point you at a mini.

http://www.everymac.com/upgrade_cards/b ... _blue.html
http://www.2ndchancepc.co.uk/macupgs.html

You could, I suppose, stick a G5 mobo and processor in your G3 case, but you'd also need the appropriate PSU for it. And you'd need to remodel the case to accept it. Cooling it would be a big issue as well.

Short answer: A G4 processor swap is as far as you can go, and it's expensive. For the cost of the chip, you could just buy a dual proc. G4, and you'll be able to fill it with up to 4 HDs, use a more modern GFX card and run Leopard. You're also not stuck with the 120GB limitation of the G3.
I know where my money would go.

Since they are only Power chips, you my get away with finding out the Power model (as apposed to the Apple branding of Gx) and find one on eBay...Unless Apple demanded that the chips be different in some way...

LU, logic/system board == motherboard, actually I've not heard the term motherboard in ages....

As I said, the pin outs between the G3 series and G4 are different. The CPU upgrades need a daughter board that mounts on the CPU socket. Even going between the 500MHz Graphite G4 and the later MDD's, the pin outs are different, you can't swap a processor from a 1.25GHz G4 into the mobo of a 500MHz G4.

The original G4 PowrMacs of the 400MhZ variety were in reality G3 systems with a G4 chip instead. The speedier G4s and later models did use different hardware. So, theoretically, you could drop a G4 chip in a G3 case. If you were interested in doing some old time tinkering, and building some kind of hybrid monster Mac, then this is fine, but I’d agree that you may be better off putting the money you were going to spend on that to a new MIni, which would give you the speed boost AND the chance to keep up with Apples OSX updates.

I guess it’s what you want to do with the hardware. I can imagine that tinkering may well be you bag, so have fun if that’s your aim for the hardware.

Anyway, this kit is what you need:
http://www.sonnettech.com/product/encore.html
If you can find them on ebay.

Which I believe I have:
http://cgi.ebay.co.uk/Sonnet-Encore-G4- ... 7C294%3A50

The price seems keen. I’ll let you decide if this is the right bit of hardware.

Thanks a lot everyone.

I've done some reading, and it seems if the firmware has been updated on the mobo, it will accept G4 chips.

Thats very cheap on Ebay Paul, thanks for linking me to it. I might purchase that.

Do post your results - I’m keen to know how this works out.

My parents have one in their B&W G3 and it works a treat.

I never ended up buying that, it ended up going for nearly £70!

I think i'm now going to try and sell my G3, which has 1.3.9 and runs it OKish, and pick up eitehr a cheap G4 or G5.

One thing I have learned though is the premium Apple have on their stuff. I mean £469 (with edu. discount) for a Mac Mini, with a 2ghz Core Duo, 1GB RAM, 80GB HDD and a GeForce 9400M GPU? I could build the same system AND buy Windows for about £150-200!

This is old, old territory, but could you build it in a box the same size?
Also, look at the refurb store too.

Plus if you ever sold it the Mac Mini would be worth much more.

True, but then again look at the Mac Pro. I'm not causing any arguments, its just Apple stuff has a big premium over it.

Anyway, I think I'm going to rip my cousin off with the G3 and make £20 off him (I got the Mac for £25) and then put that towards a Mac Mini G5 I might be buying off a mate. Will this be much much quicker than my pappy old G3?

Cheers everyone!

Is there a Mac Mini G5? I thought there was only the G4 and the Intel versions?

That's correct - there wasn't a G5 Mini. Only G4 and Intel. Probably for the same reason there wasn't a G5 Apple laptop - PPC G5 chips were meant to get pretty hot and so, couldn't work in environments with not much cooling. I'm not sure if there were other reasons but that seems like the obvious one to me.

Adam, you may want to take a look at the Powermac G5 - it still offers fairly good performance today and you could probably pick one up at a fairly reasonable price. The downside is though, it can't run Snow Leopard - you'd need an Intel processor to do that.