Angelgreat
Well-known member
Hello, I'm thinking about getting a iMac G3 slot loader, but I was wondering if the CPU can be upgraded to a G4. I know it's soldered on directly, but would it be possible to put a 2ghz G4 in it's place?
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Is it possible to upgrade a iMac G3 slot loader to a 2ghz G4?
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Angelgreat
Well-known member
Hello? what's the fastest g4 cpu that can work on the iMac G3?
3lectr1cPPC
Well-known member
The fastest G4 upgrade was the FastMac G4/550 which gave you a 550MHz G4 by swapping out your motherboard with a new one. I don't think installing such a fast processor would be possible, or very practical for that matter.
Here's a page on iMac G3 processor upgrades: https://everymac.com/upgrade_cards/by_system/imac.html
Here's a page on iMac G3 processor upgrades: https://everymac.com/upgrade_cards/by_system/imac.html
Angelgreat
Well-known member
Wait, did they just use a regular slot loader iMac G3 motherboard and just switch out the cpu?
By "new motherboard" it's worth noting that based on the description on everymac, what the vendor was probably doing was buying used imacs, G4 swapping the CPUs, and then swapping those boards to customers as a source of new motherboards to do the swap on. It's just that on previous generations of G3s, the CPUs came on modules so you could swap just the module or build a new module.
It looks like, to avoid the fact that a G3@600 or @700 would probably be faster than a G4@550 for most things, they didn't bother doing this upgrade to those models.
This is one of those things that might be possible but for myriad reasons, nobody bothered with.
Unfortunately if you want a 2GHz G4 your best option is probably to buy an iMac G4 or eMac G4, a PowerMac G4, or, if you just want to run OSX/PPC software real fast, any Intel Mac that runs up through to 10.6.
@Angelgreat - genuine question here, what Macs have you used up to this point? In particular, are you looking for OS 9 or OS X and what have you used OS 9 on before?
Some of this is going to depend on what overall experience you're looking for but for my part, Mac OS 9 basically feels as fast as it ever will on "literally any G3" with the qualification that my only G3s have ever been systems that started as G3s.
If you want an iMac G3, I think you should get one confident in the fact that Mac OS 9, most desktop productivity and multimedia consumption software, and most period games will work great on it. (People talk about buying like high end G4s for OS 9 gaming but the reality is that games had to be aimed at iMacs because imacs is what most Mac users who wanted to play games had.)
If you want something to do "compute" on, like, serious business statistics or math software, software development, video rendering, etc etc then, yeah, a 2GHz PowerMac G4 probably makes a lot of sense. QEMU on a modern/fast computer might also make sense, especially if you've got a reasonably well developed filesharing workflow, even though QEMU can fall behind in floating point in particular. But, at everyday stuff? QEMU on my i5-2300 gets roughly G3/300 performance at integer.
Related to this is that Mac OS 9 doesn't really feel any faster on faster Macs. I think I've mentioned this before but on hand right now I have Beiges /266 and /300, an iMac/400, an iBook/366, a QS'02/800, a TiBook/1000, and I'm probably getting a machine. To me, they all feel the same speed. Heck, most of the software I run on all those runs fine on even older machines, although once you start getting into the realm of 604 PCI PowerMacs under 300MHz or so, 7.6.1 and 8.1 are faster than 9.1 is faster on that hardware. (9.1's not unusable but it requires a lot more patience on a 7200/90 than it does on a 9600/300, for example. Heck, 9.1 even runs on 6100s and 6200s, but, again, you'll spend more time waiting for things to happen there, especially if you don't max out the ram.)
I know I beat the drum of "maybe the vintage Mac you have is good enough" and "no bad Macs" a little loudly, but it's a genuinely held belief. iMac G3s are great machines (when they're not falling apart, which, is admittedly a thing they do, because structural plastic) and they run OS 9 really well. The later ones should also be serviceable for basic usage in OS X but if you want an OS X machine having things like dual CPUs, better graphics, 2 gigs of RAM, or, just "an intel CPU" become more meaningful boosts than they are on OS X.
Upgrades are fun, but some of these upgrades aren't really reasonable and/or by the time, say, 2GHz G4s were a thing, Intel Macs were already common so nobody bothered eveloping adaptations for older/cheaper systems. The only reason PowerMac G4s got 1.8-2GHz G4 upgrades new is because they were cheap and easy to build relative to the cost of a new Pro Mac and because there was some hardcore PPC/Intel trutherism happening at the time, similar to (but arguably more intense than today's Intel/M1 truthing.)
It looks like, to avoid the fact that a G3@600 or @700 would probably be faster than a G4@550 for most things, they didn't bother doing this upgrade to those models.
This is one of those things that might be possible but for myriad reasons, nobody bothered with.
Unfortunately if you want a 2GHz G4 your best option is probably to buy an iMac G4 or eMac G4, a PowerMac G4, or, if you just want to run OSX/PPC software real fast, any Intel Mac that runs up through to 10.6.
@Angelgreat - genuine question here, what Macs have you used up to this point? In particular, are you looking for OS 9 or OS X and what have you used OS 9 on before?
Some of this is going to depend on what overall experience you're looking for but for my part, Mac OS 9 basically feels as fast as it ever will on "literally any G3" with the qualification that my only G3s have ever been systems that started as G3s.
If you want an iMac G3, I think you should get one confident in the fact that Mac OS 9, most desktop productivity and multimedia consumption software, and most period games will work great on it. (People talk about buying like high end G4s for OS 9 gaming but the reality is that games had to be aimed at iMacs because imacs is what most Mac users who wanted to play games had.)
If you want something to do "compute" on, like, serious business statistics or math software, software development, video rendering, etc etc then, yeah, a 2GHz PowerMac G4 probably makes a lot of sense. QEMU on a modern/fast computer might also make sense, especially if you've got a reasonably well developed filesharing workflow, even though QEMU can fall behind in floating point in particular. But, at everyday stuff? QEMU on my i5-2300 gets roughly G3/300 performance at integer.
Related to this is that Mac OS 9 doesn't really feel any faster on faster Macs. I think I've mentioned this before but on hand right now I have Beiges /266 and /300, an iMac/400, an iBook/366, a QS'02/800, a TiBook/1000, and I'm probably getting a machine. To me, they all feel the same speed. Heck, most of the software I run on all those runs fine on even older machines, although once you start getting into the realm of 604 PCI PowerMacs under 300MHz or so, 7.6.1 and 8.1 are faster than 9.1 is faster on that hardware. (9.1's not unusable but it requires a lot more patience on a 7200/90 than it does on a 9600/300, for example. Heck, 9.1 even runs on 6100s and 6200s, but, again, you'll spend more time waiting for things to happen there, especially if you don't max out the ram.)
I know I beat the drum of "maybe the vintage Mac you have is good enough" and "no bad Macs" a little loudly, but it's a genuinely held belief. iMac G3s are great machines (when they're not falling apart, which, is admittedly a thing they do, because structural plastic) and they run OS 9 really well. The later ones should also be serviceable for basic usage in OS X but if you want an OS X machine having things like dual CPUs, better graphics, 2 gigs of RAM, or, just "an intel CPU" become more meaningful boosts than they are on OS X.
Upgrades are fun, but some of these upgrades aren't really reasonable and/or by the time, say, 2GHz G4s were a thing, Intel Macs were already common so nobody bothered eveloping adaptations for older/cheaper systems. The only reason PowerMac G4s got 1.8-2GHz G4 upgrades new is because they were cheap and easy to build relative to the cost of a new Pro Mac and because there was some hardcore PPC/Intel trutherism happening at the time, similar to (but arguably more intense than today's Intel/M1 truthing.)
Angelgreat
Well-known member
Well @Cory5412 , a few. I never owned one, but I have used them in school. In middle school, one of the computer labs had 2009 education Intel iMacs running 10.7 Lion. They had eMacs, but had already replaced them by the time I went to Middle School. I didn't see any iMacs in High School, but in College, there are some Retna iMacs running Big Sur, plus some for sale. I haven't used a PowerPC Mac before, but I have used Sheepshaver.
Also, I was just asking what's the fastest G4 that can work on the G3 because I'm considering getting one and doing some upgrades to it.
Yes.
So here’s the long and short of it: the first couple versions of the G4 (7400, 7410) were pin compatible with the ‘original’ G3, the 750. (750 with no letters after the number.) This means you can literally just desolder the 750 and drop in a 7410; presumably you‘ll also want to tweak the bus multiplier settings, but that it, that’s all it takes to make this upgrade.
The problem here is that both of these CPUs max out at around 500mhz. (600mhz is about the hard limit.) So, no, you can just go to 2ghz with a CPU swap; the 7410 won’t go anywhere close to that and the 4750 and later are no longer pin compatible. Also the last G3 iMacs used the 750CX and related IBM G3 variants that are *also* not pin compatible with either the 750 nor *any* G4, so the window for upgrading without serious work on either a whole new motherboard or some kind of nightmarish BGA interposer board also closes for them.
Frankly for OS 9 a G4 upgrade to a CPU close to the same MHz is mostly a lateral move, there simply isn’t much classic software that needs Altivec. It’s arguably worth it for OS X, but since OS X also hugely benefits from a Radeon or better video card, not found in G3 iMacs, a better computer makes way more sense.
To add: We shouldn't stop dreaming and it's fine to want these things, heck, I would love an iMac G3 with a 2GHz G4 installed in it, I just think that these machines are also great as-is and if you're asking these questions because you're making a purchasing decision, my point is: just get something and see what it's like, it might not be that bad!
That sounds like fun! It's also radically different from how Mac OS 9 performs.
It's worth noting that Mac OS 9 is basically system 7 with a couple components updated and a facelift. At its very core, Mac OS 9 can achieve its peak performance on, like I said, a G3/233. Meanwhile, Macs kept getting faster (albeit not as fast as Intel computers) mostly because OS X did genuinely need more.
In OS 9, the only reasons to run something faster than a G3/233 are:
Here's what I think you should do: Get a system you think you'd like, or, to be honest iMac G3s in good condition are sort of becoming thin on the ground because of structural plastics -- get any iMac G3 or whatever and then use it for a bit, Live with it, play games on it, install Word 2001 or whatever it is you want to do and then see what you think you need.
If you genuinely need (or just want) a faster OS 9 experience, the most economical way to get it is a TiBook G4, PowerMac G4, or one of the versions of the eMac G4 that can boot OS 9 directly. I mostly wouldn't bother with unofficial 9 booting except perhaps on the mini G4 whose 167MHz bus and up to 1.5GHz CPU makes it about as fast as a 2GHz-ugpraded QuickSilver anyway but Mini G4s are expensive because they're small, cute, low-power, and also because they run some Amiga software.
And, yeah, imac G3s will run OS X but OS X is meaningfully better on newer/better machines that have better graphics, higher ram ceilings, duallies and altivec, so I just run 9 exclusively on my own G3s.
That sounds like fun! It's also radically different from how Mac OS 9 performs.
It's worth noting that Mac OS 9 is basically system 7 with a couple components updated and a facelift. At its very core, Mac OS 9 can achieve its peak performance on, like I said, a G3/233. Meanwhile, Macs kept getting faster (albeit not as fast as Intel computers) mostly because OS X did genuinely need more.
In OS 9, the only reasons to run something faster than a G3/233 are:
- It's what you could find
- You already had it on hand
- More G4/800s exist than G3/233s, just due to the way the Mac business was scaling up from 1997 to 2002
- You have games that need a Rage 128 and an entire new Mac is cheaper than putting one in a beige G3, or your Mac is a PowerBook/iBook/iMac (Although all iBooks have 8-meg Rage128s IIRC, so that's a good starting point for games.)
- If you need more frames just turn down the resolution - I didn't play a game at over 640x480 until like 2007
- You're playing OSX-era games that really want Radeons and were backported/carbonized to 9 and they need more oomph
- a game can "really want a radeon", have a radeon, and still run best at 640x480
- You're doing multimedia content creation or technical computing and render time is of concern
- depending on what it is you're doing most of this software is faster, more reliable, and takes better advantage of multi-tasking, more ram, or dual CPUs under OS X, the main exception as far as I know is development software for OS 9
- You need to dual boot with OS X and/or you're really talking about Classic Mode.
Here's what I think you should do: Get a system you think you'd like, or, to be honest iMac G3s in good condition are sort of becoming thin on the ground because of structural plastics -- get any iMac G3 or whatever and then use it for a bit, Live with it, play games on it, install Word 2001 or whatever it is you want to do and then see what you think you need.
If you genuinely need (or just want) a faster OS 9 experience, the most economical way to get it is a TiBook G4, PowerMac G4, or one of the versions of the eMac G4 that can boot OS 9 directly. I mostly wouldn't bother with unofficial 9 booting except perhaps on the mini G4 whose 167MHz bus and up to 1.5GHz CPU makes it about as fast as a 2GHz-ugpraded QuickSilver anyway but Mini G4s are expensive because they're small, cute, low-power, and also because they run some Amiga software.
And, yeah, imac G3s will run OS X but OS X is meaningfully better on newer/better machines that have better graphics, higher ram ceilings, duallies and altivec, so I just run 9 exclusively on my own G3s.
jeremywork
Well-known member
A few things worth mentioning from my experience:
To Cory's point, I find little practical performance difference between my 500MHz Pismo G3 and my 1000MHz TiBook G4 in OS 9; though quite a significant difference in OS X. I did have a Pismo with a 7410 which I ran at 600MHz until the Altivec unit burned up and now freezes the system the moment an instruction is sent to it. I've since run another at 500MHz without issue, and would probably be fine at 550 but I'm inclined to leave it alone so I can use it in hot weather without worrying. While the Altivec is super fast for things that use it, it should be noted that a few functions of the 7400/7410 are actually slower than the G3 at the same clock speed.
Also, Sheepshaver on even the fastest Intel Mac runs much more slowly than one might expect. IIRC some of the faster Core 2 Duos could bench similarly to a 100-120MHz G3 in Sheepshaver.
And yes, absolutely nothing wrong with shooting for the moon
I own quite a few 'unreasonably upgraded' machines and they're fun to study and mess with, just know that the value proposition really isn't usefulness as much as novelty. My Dual 1.8GHz Quicksilver runs OS 9 very fast, but if I were to blind split test with a factory Dual 1.0 it would be difficult to pick out which is which without booting to OS X.
To Cory's point, I find little practical performance difference between my 500MHz Pismo G3 and my 1000MHz TiBook G4 in OS 9; though quite a significant difference in OS X. I did have a Pismo with a 7410 which I ran at 600MHz until the Altivec unit burned up and now freezes the system the moment an instruction is sent to it. I've since run another at 500MHz without issue, and would probably be fine at 550 but I'm inclined to leave it alone so I can use it in hot weather without worrying. While the Altivec is super fast for things that use it, it should be noted that a few functions of the 7400/7410 are actually slower than the G3 at the same clock speed.
Also, Sheepshaver on even the fastest Intel Mac runs much more slowly than one might expect. IIRC some of the faster Core 2 Duos could bench similarly to a 100-120MHz G3 in Sheepshaver.
And yes, absolutely nothing wrong with shooting for the moon
I own quite a few 'unreasonably upgraded' machines and they're fun to study and mess with, just know that the value proposition really isn't usefulness as much as novelty. My Dual 1.8GHz Quicksilver runs OS 9 very fast, but if I were to blind split test with a factory Dual 1.0 it would be difficult to pick out which is which without booting to OS X.
Not an iMac, but I did (technically still do, I should see if it still works) have a B&W G3 that came with a 400Mhz G3; I swapped straight over a 400Mhz G4 ZIF card (I could have messed with the jumpers to try to make it go faster, but as I said, 500mhz probably would have been the hard limit), and I can say straight up there was *zero* difference under OS 9. Zippo. Nada. Maybe there's a piece of software that would be able to take advantage of it, but I didn't have any.
For OS X, like I said, the difference was significant; things like those "zooming the window out of the dock" effects were noticeably improved. But because adding Altivec didn't also magically add Quartz Extreme rendering (Radeon/GeForce GPU or better PLUS AGP bus) the machine still sucked bilgewater compared to even the same speed Sawtooth with a "real" Radeon. (I actually did add a Radeon card, a PCI Radeon 7000, but the 7000 is both well known for only being about 50% faster than the Rage 128 for GL stuff, and, again, no Quartz Extreme. There is a software patch to enable it on B&W G3s/Yikes G4s, but it has... side effects.) No iMac G3 came with better than a Rage 128, so they are genetically poor OS X machines. So... again, this is why I question the point of a G4 upgrade for iMacs, period: they're cruddy OS X machines because of the video card, which you *cannot* upgrade, and there's not much software for OS 9 that uses Altivec. QED.
If you want one because it's pretty and you want a nostalgic OS 9 box by all means buy one if you find one that still has a working monitor and isn't crumbling to pieces. I would just strongly recommend enjoying it *as is*.
For OS X, like I said, the difference was significant; things like those "zooming the window out of the dock" effects were noticeably improved. But because adding Altivec didn't also magically add Quartz Extreme rendering (Radeon/GeForce GPU or better PLUS AGP bus) the machine still sucked bilgewater compared to even the same speed Sawtooth with a "real" Radeon. (I actually did add a Radeon card, a PCI Radeon 7000, but the 7000 is both well known for only being about 50% faster than the Rage 128 for GL stuff, and, again, no Quartz Extreme. There is a software patch to enable it on B&W G3s/Yikes G4s, but it has... side effects.) No iMac G3 came with better than a Rage 128, so they are genetically poor OS X machines. So... again, this is why I question the point of a G4 upgrade for iMacs, period: they're cruddy OS X machines because of the video card, which you *cannot* upgrade, and there's not much software for OS 9 that uses Altivec. QED.
If you want one because it's pretty and you want a nostalgic OS 9 box by all means buy one if you find one that still has a working monitor and isn't crumbling to pieces. I would just strongly recommend enjoying it *as is*.
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