Possible PowerBook G5 discovered!

[Bug-Creator]

A while back we (aka those MorphOS people) did some testing with running xz on the MorphOS3.19 ISO in RAM.

1.67GHz PowerBook did in 10:22
2.5GHz G5 did it in 6:43 / 6.55 (both PCIe systems with only 1 CPU and offcourse only running 1 core)
Pegasos2-G4@1.8GHz did in 21:11 (that is a really slow RAM interface)
Now guess what was the winner?
A 1.6GHz Mirari in 6:14 so a really weak CPU at a low clock, just with a very good DDR3 interface.

Just for good measure:
My M1Max (using all 8+2 cores) did it in 15:97


well seconds not minutes on that one

 

[barracuda156]

While aftermarket G4s did have 1.8 and even 2.0GHz clocks which would allow for such a comparison it seems a disservice to do so, especially as these G4 upgrades are extremely rare and cost-probihitive.

Yeah, at those prices you can get late 2005 G5, which gonna roast any G4. (I wouldn’t mind dual G4 2.0 in a PowerBook though.)

 

[barracuda156]

A while back we (aka those MorphOS people) did some testing with running xz on the MorphOS3.19 ISO in RAM.

Did you try with macOS? MorphOS may simply not be optimized for G5.

1.67GHz PowerBook did in 10:22
2.5GHz G5 did it in 6:43 / 6.55 (both PCIe systems with only 1 CPU and offcourse only running 1 core)

Now try compiling gcc LOL

Pegasos2-G4@1.8GHz did in 21:11 (that is a really slow RAM interface)
Now guess what was the winner?
A 1.6GHz Mirari in 6:14 so a really weak CPU at a low clock, just with a very good DDR3 interface.

A board 20 years newer than the Quad did marginally better per-core? )

Just for good measure:
My M1Max (using all 8+2 cores) did it in 15:97
well seconds not minutes on that one

LOL

FWIW, I actually saw a real-life case when G5 Quad was faster than M1. (Running a test-suite for some port, I forgot now which one.)

 

[ervus]

G5s are much faster than G4s at the same CPU clock.

I would disagree with this. The G5 has faster RAM bandwidth and some 64-bit instructions. In other respects I think the G4 is superior. There is a thread here on compiling tff and I tested some different machines and reported the results. A dual 2GHz G4 was actually slightly faster than a dual 2GHz G5.

Plus, a G4 fits on my lap and is what I'm posting this with.

 

[barracuda156]

A dual 2GHz G4 was actually slightly faster than a dual 2GHz G5.

Well, I don’t have a dual G4 to try, but I’d bet money on a G5.

Plus, a G4 fits on my lap and is what I'm posting this with.

This is an advantage, admittedly. (As a side effect this, unfortunately, makes PowerBooks hardly usable for anything beyond lite tasks.)

 

[Bug-Creator]

A board 20 years newer than the Quad did marginally better per-core? )

A board that uses an 1.6GHz SoC based on cores that are barely updated since G3 (if not even G2)....

But yeah your mileage may vary depending on the test used, but I also remember that some 15 years ago when the X1000 (P6T) came out various test were made while running Linux. One of the them was a Blender thing and my 2x1.8GHz QuickSilver got the same results as the X1000 (also 1.8GHz) and DualCPU G5s were in the same ballpark adjusted for clock. Despite the QS having a really crappy RAM interface not even fully suitable for the single 800MHz G4 it once shipped with it.

 

[Nullcaller]

Unfortunately there isn't any stock configuration of G4s and G5s that match clock speeds-- no G4 had a 1.60GHz clock nor anything faster than 1.67.

There might be a way, though... Think outside the box. The G5s have a feature Apple called 'bus slewing' which as far as I know effectively just downclocks the CPU to half its nominal frequency.

So what you could probably do, is compare a 1.6 GHz iMac G5 with an 800 MHz Early 2002 Power Mac G4, or a Dual 2.0 GHz Late 2005 Power Mac G5 with a Dual 1.0 GHz Early 2002 Power Mac G4.

Though it would probably be more efficient to just run the same benchmarks on a single-core G4 and a single-core G5, and then calculate adjusted numbers (performance/GHz). That's how architectures are always assessed, it's not cheating or data manipulation. The most widely used (and abused) performance metric is probably DMIPS per MHz, which is Dhrystone Millions of Instructions Per Second per processor clock frequency. Now, Dhrystone is a bad benchmark when it comes to real performance. But the principle is valid, and is even used in SPEC benchmarks.

 

[NewbiePPC]

This discussion reminded me this video.

 

[wm2]

A 1.6GHz Mirari in 6:14 so a really weak CPU at a low clock, just with a very good DDR3 interface.

There will be a larger CPU with Altivec 2.0 (e6500). Personally, I'm only interested in this larger CPU (with overclock). If there will be a good hardware video decoding, it would increase its value again, despite the weak processor. Anyway, this performance is dwarfed by an average early 2010 PC.

MorphOS Mirari NVME

 

[Nullcaller]

This discussion reminded me this video.

It's honestly unbelievable how in my borderline autistic obsession with the G5 YouTube has never allowed me to find this video. Thank you for linking this.

 

[Bug-Creator]

There will be a larger CPU with Altivec 2.0 (e6500).

There could be a SoC with Altivec depending on lots of things that simply aren't know yet.
While Altivec and a few extra 100MHz sounds nice I am quite happy with what I got.

As for video decoding, even the ancient GPUs used would do a much better job at that.

And yes this is a ca. 201x SoC aimed at embedded use case so no surprise it performs just like that.

 

[LightBulbFun]

So... Ahem... I'm a bit sorry to resurrect this old thread. But, you know, I think I may have found something important. You know, for quite a very long time, I've been searching for a Power Mac G5 schematic, or at least a glimpse of it, maybe a confirmation that it exists at all... What I've been finding instead is mostly iMac G5 schematics, with the occasional iMac G4 thrown in for a bit of fun.

You can always tell what you're looking at, because the G4-based Macs all have the big 'Intrepid' chip in the middle of their system block diagram, along with some sort of 'Apollo' CPU, while the G5 CPU is always labelled 'Neo 10s' and is connected to either 'U3lite' (because those are iMac schematics, not the Power Mac with full-blown 'U3') or 'Kodiak' (which is the IBM-designed chip used in some of the later G5-based systems, also affectionately known as 'U4'). 'Shasta' and 'Vesta' are also always present in G5-based designs, because those are the actual chips implementing on-board IO, like USB, Ethernet, Firewire, etc.

So yeah, I've been searching for a possible G5 schematic, downloading everything I find along the way... But today I've found something that immediately caught my eye. Actually, I found it earlier, it's just that I didn't come around to downloading and looking at it properly before.

There was this one schematic which didn't seem to relate to anything else. The iMacs are usually clearly labelled 'IMG5', 'IMAC G5' or something like that. Sometimes they have some boring names, like 'Seedy' or 'Sinclair'. But this schematic, it was simply titled 'LINK'. Now that's an intersting name. And no iMac label in sight. Also, the schematic was marked as 'EVT'. That, ladies, gentlemen and all in between, stands for 'Engineering Validation Test', and is the earliest of the prototyping stages.

Now, bearing all of the above in mind, I invite you now, to take a look at this:

View attachment 2590051

First thing... Okay, 'NEO 10S', we've got a G5-based Mac. 'U3LITE', one of the earlier ones. 'ATI M11' integrated graphics, so not a Power Mac, goddamit.

Second thing... SODIMM? None of the iMac G5 schematics have SODIMM slots on them. But, you know, I don't have any idea what Apple's product stack looked like in mid 2000s, maybe they had an iMac with SODIMM slots. Who knows? Not me.

Third thing... Okay, 'U3LITE' connected to 'SHASTA', that's okay, everything's as usual... But then there's USB 2.0, and w- what's that? 'USB Trackpad'? 'KB LED'? ('KB LED' commonly stands for keyboard LED) Well, maybe there's some sort of weird thing going on where they were including trackpads/keyboards with the G5 iMacs, and they decided to put them on the block d-

Don't tell me there's a block titled 'Battery Connector' in the top-left corner that I haven't noticed because I was looking at the CPU before looking at everything else... ... ... Yeah, there is...

...

...

Okay, so one more thing before I leave you with your own thoughts about this, because I'm sure you might have plenty. Here's the next sheet in the schematic:

View attachment 2590059

Here, apparently, Apple engineers were trying to make sense of the power draw of this whole thing. Now, this is just fun, and confirms the notion that PBG5 was scrapped for power draw reasons. Not to mention, it probably wasn't that good in terms of performance either, since the G5 chip would have probably been running at 0.6-1.2 GHz (PI bus is running at 600 MHz as per the first image, core frequency is an integer multiple of that, but clearly not 1.8).

The schematic in question is attached to this message.

the least you could do is give me some credit man

https://forums.macrumors.com/threads/powerbook-g4-with-official-7448.2383142/?post=32030271#post-32030271

 

[Nullcaller]

the least you could do is give me some credit man

https://forums.macrumors.com/threads/powerbook-g4-with-official-7448.2383142/?post=32030271#post-32030271

Oh wow! Honestly, it didn't even occur to me to check if someone had posted schematics for PBG5 before. The schematics I found are probably better, cause they don't have the annoying watermark, but yours have boardviews attached which is just so much more interesting!

With those boardviews, it would probably be feasible to try and re-create the PBG5 board. Y'know, pull up some datasheets to make sure you're doing well on signal integrity, replace power circuitry with a modern equivalent, use a PCB manufacturing service to make the board and place most of the components, steal the chips from a broken PMG5, and et voila, you have a brand new PowerBook G5.

Now, none of it is easy, nor would I like to in any way suggest that it is. But it is technically feasible. Which is the best kind of feasible.

 

[barracuda156]

Oh wow! Honestly, it didn't even occur to me to check if someone had posted schematics for PBG5 before. The schematics I found are probably better, cause they don't have the annoying watermark, but yours have boardviews attached which is just so much more interesting!

With those boardviews, it would probably be feasible to try and re-create the PBG5 board. Y'know, pull up some datasheets to make sure you're doing well on signal integrity, replace power circuitry with a modern equivalent, use a PCB manufacturing service to make the board and place most of the components, steal the chips from a broken PMG5, and et voila, you have a brand new PowerBook G5.

Now, none of it is easy, nor would I like to in any way suggest that it is. But it is technically feasible. Which is the best kind of feasible.

I would love to have G5 SCB by the way. That would destroy Mirari yet be portable.

 

[Anonymous Freak]

Seeing that this thread has revived, I have, in the many years since this thread started, had occasion to be coworkers with someone who actually worked on the PowerBook G5. They confirm that the prototype pictured here was used for both dual-G4 and single-G5 prototyping.

The PowerBook G5 never got much further than this prototype. They did make one in a more conventional PowerBook G4 shell, but instead of it being "quadruple thick" like some Photoshops, it just had a hole cut in the bottom with a big-ass heatsink sticking out the bottom.

The CPU itself wasn't the problem, the fact that the chipsets were all made for desktops meant that the chipset drew basically the same power as the low-power CPU itself. Apple did start the process of designing their own custom lower-power chipset, but it never even made it to working samples, much less close to production.

Plus, the G5 at low enough power ratings to be useful for a laptop wasn't any faster than a G4 in the same power envelope. On top of it, the G5 was actually *unstable* at low voltages, even at low GHz. Minimum stable speed was 1.4 GHz, and still drew more power than a G4 at 1.66 GHz, while being slower than it at nearly everything. (G5 was an IBM "POWER4" workstation/server CPU with AltiVec extensions from the G4 added. It was never meant to be power-efficient.)

By the time IBM could have had low-enough power CPUs and chipsets, Intel's roadmap already had them ready to outpace IBM with the Core 2 Duo.

Then IBM basically told Apple "we're not building you anything custom, if it isn't already on our roadmap for our own use, we won't make it." Which ruled out low-power G5s altogether.

Literally the only advantage G5 had over G4 in the mobile space was "64-bit" - something that didn't matter until quite a few years later.

 

[840quadra]

Seeing that this thread has revived, I have, in the many years since this thread started, had occasion to be coworkers with someone who actually worked on the PowerBook G5. They confirm that the prototype pictured here was used for both dual-G4 and single-G5 prototyping.

The PowerBook G5 never got much further than this prototype. They did make one in a more conventional PowerBook G4 shell, but instead of it being "quadruple thick" like some Photoshops, it just had a hole cut in the bottom with a big-ass heatsink sticking out the bottom.

The CPU itself wasn't the problem, the fact that the chipsets were all made for desktops meant that the chipset drew basically the same power as the low-power CPU itself. Apple did start the process of designing their own custom lower-power chipset, but it never even made it to working samples, much less close to production.

Plus, the G5 at low enough power ratings to be useful for a laptop wasn't any faster than a G4 in the same power envelope. On top of it, the G5 was actually *unstable* at low voltages, even at low GHz. Minimum stable speed was 1.4 GHz, and still drew more power than a G4 at 1.66 GHz, while being slower than it at nearly everything. (G5 was an IBM "POWER4" workstation/server CPU with AltiVec extensions from the G4 added. It was never meant to be power-efficient.)

By the time IBM could have had low-enough power CPUs and chipsets, Intel's roadmap already had them ready to outpace IBM with the Core 2 Duo.

Then IBM basically told Apple "we're not building you anything custom, if it isn't already on our roadmap for our own use, we won't make it." Which ruled out low-power G5s altogether.

Literally the only advantage G5 had over G4 in the mobile space was "64-bit" - something that didn't matter until quite a few years later.

Interesting stuff, but the end doesn't make sense with IBM, especially since they were in the process of developing Cell with Sony and Toshiba. Perhaps (as it happens because they can be a pain to deal with) IBM had lost interest in dealing with Apple by the time Cell matured.

IBM was literally trading business partners, dropping AIM (Apple IBM Motorola) for some new friends to play with.

 

[Anonymous Freak]

Interesting stuff, but the end doesn't make sense with IBM, especially since they were in the process of developing Cell with Sony and Toshiba. Perhaps (as it happens because they can be a pain to deal with) IBM had lost interest in dealing with Apple by the time Cell matured.

IBM was literally trading business partners, dropping AIM (Apple IBM Motorola) for some new friends to play with.

My source doesn't know any of the major business side stuff behind IBM's decision, only what Apple was told.

It was likely that they were happy to deal with Cell and Xenon (PS3 and Xbox 360) because they were fixed targets. Develop once, maybe do a die-shrink for power savings later, and that's it. Apple would have insisted on constant newer faster lower-power CPUs for years.

And the fact that both PS4 and Xbox One switched to x86 kind of shows how IBM simply didn't care enough to try to keep them past the one CPU cycle.

 

[840quadra]

My source doesn't know any of the major business side stuff behind IBM's decision, only what Apple was told.

It was likely that they were happy to deal with Cell and Xenon (PS3 and Xbox 360) because they were fixed targets. Develop once, maybe do a die-shrink for power savings later, and that's it. Apple would have insisted on constant newer faster lower-power CPUs for years.

And the fact that both PS4 and Xbox One switched to x86 kind of shows how IBM simply didn't care enough to try to keep them past the one CPU cycle.

All fair points.

Back in the AIM days, I am still curious as to why Motorola / Freescale didn't do more to carry that torch, but feel IBM had a big part in controlling where the Power architecture was used or implemented.

Considering Steve Jobs's early dislike for Big Blue, I always thought it was funny that AIM lasted as long as it did!

 

[Smithwick’s]

(G5 was an IBM "POWER4" workstation/server CPU with AltiVec extensions from the G4 added. It was never meant to be power-efficient.)

Literally the only advantage G5 had over G4 in the mobile space was "64-bit" - something that didn't matter until quite a few years later.

I think these are important points to make in the entire PPC discussion. It really shows when you explore alternative OSes for G5s vs G4/3s. The G5 seems to be "PowerPC" in name only, otherwise as you point out it looks, behaves, and generally vibes like POWER. To that end as much as Apple wanted to shoehorn a G5 into a PowerBook I wish they had focused on doing more with the G4, which comes off as more purely "PowerPC" in the first place. A dual CPU or dual core PBG4 would have been killer to have, especially if it was a later-revision like the 1.67GHz.

Of course, this gets into the whole rumor mill surrounding the late-run G4s and their apparent hobbling by Apple. My understanding is that they decided against switching to newer CPUs for the 1.67GHz runs in part because they would have outperformed at least the initial Intel offerings which were already in the pipeline and which Apple needed to market as being leaps-and-bounds improvements.

 

[Bug-Creator]

A dual CPU or dual core PBG4 would have been killer to have, especially if it was a later-revision like the 1.67GHz.

I'm pretty sure there were at least some picture of prototypes leaked way back when.
But same problem as with the G5, too much power draw and heat to make sense.

Motorola (I think they were still called that at the time) showed little interest (or just weren't able to) in pushing the G4 further and had already canned all the plans they had for their own "G5".

The only "plausible" candidate would have been the P6T but that turned out too little too late.

 

[rampancy]

Seeing that this thread has revived, I have, in the many years since this thread started, had occasion to be coworkers with someone who actually worked on the PowerBook G5. They confirm that the prototype pictured here was used for both dual-G4 and single-G5 prototyping.

The PowerBook G5 never got much further than this prototype. They did make one in a more conventional PowerBook G4 shell, but instead of it being "quadruple thick" like some Photoshops, it just had a hole cut in the bottom with a big-ass heatsink sticking out the bottom...

Fascinating. This reminds me a lot of the Architosh stories about the rumored Motorola 7500 "G5". Supposedly, prototype systems easily outperformed contemporary Athlon and Pentium CPUs, but the CPU consumed too much power and generated too much heat to be viable. Supposedly one system even cooked itself to death during testing. If the stories even are remotely true I'd love to see a test machine one day surface in the wild, like with the cancelled Power Express machine, or the Dual-G4 PowerBook. Seeing that machine makes me wonder how hard it would have been to make a dual-core 7450.

Back in the AIM days, I am still curious as to why Motorola / Freescale didn't do more to carry that torch, but feel IBM had a big part in controlling where the Power architecture was used or implemented.

Considering Steve Jobs's early dislike for Big Blue, I always thought it was funny that AIM lasted as long as it did!

I always saw it as a profit issue. For Motorola/Freescale, it would have made a lot more sense to develop the PPC as a product for the embedded market, with much greater potential to attract multiple customers and deliver better return on investment, as opposed to developing a CPU and ISA solely for one specific customer (Apple, in this case). For IBM it made commercial sense to develop PPC in the opposite direction for their own HPC/server products. In either case, whether it was the e600 or the POWER5, the PPC roadmap wasn't going to yield Apple the CPUs they needed to make something like the MacBook Air.

In an alternate universe, PPC Windows NT and PPC OS/2 would have succeeded and with CHRP, companies like Dell, HP, Gateway 2000 and Compaq would have made PPC machines or even Mac clones (assuming Apple had pulled off managing the clone program well, a big "if"), expanding the desktop PPC market and giving AIM the commercial market it needed to grow and scale the PPC further.

My understanding is that they decided against switching to newer CPUs for the 1.67GHz runs in part because they would have outperformed at least the initial Intel offerings which were already in the pipeline and which Apple needed to market as being leaps-and-bounds improvements.

IIRC, I remember reading that Apple didn't choose to use the more powerful 7457 for the PBG4 because its larger L3 cache would have driven up costs; the cacheless 7447 was apparently "good enough" for Apple.

I have no doubt that clock-for-clock the improved 7448 would have compared well to a Core Solo CPU of equivalent speed, but I'm skeptical that it would have significantly outperformed a Core Duo.

 

[Bug-Creator]

I have no doubt that clock-for-clock the improved 7448 would have compared well to a Core Solo CPU of equivalent speed, but I'm skeptical that it would have significantly outperformed a Core Duo.

The CoreSolo was only used in the absolute low end (and only for the very 1st generation) and had the benefit of not needing an extra GPU. Sure Intel's iGPUs of that time sucked big time but for the MacMini it was good enough.

CoreDuo at 1.83GHz had much higher performance and it would have needed 2 G4s (or 1 going well beyond 2GHz) to compete. Which just wasn't feasible.

On top of that, the Mini got spec-bumped just 6 months later and by the end of 2006 Core2Duo appeared, so even if Motorola/IBM/PASemi/... had some better PPC to offer for Mid2006 PowerBooks Apple would have been back in the same situation in 2007.

 

[rampancy]

On top of that, the Mini got spec-bumped just 6 months later and by the end of 2006 Core2Duo appeared, so even if Motorola/IBM/PASemi/... had some better PPC to offer for Mid2006 PowerBooks Apple would have been back in the same situation in 2007.

Indeed. Reviewing some old benchmark tests including 7447a and Core Solo equipped Macs shows the CS handily outperforming the G4, and it seems unlikely that the 7448 would have faired much better.

As someone else noted, the decision to not use a higher performing G4 was likely also influenced by a desire to not use engineering time and resources on a short-lived product.