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DarkSel

macrumors 6502
Original poster
Dec 22, 2012
278
81
So my Powerbook G4 12" has 2 USB 2.0 ports, and I used one of them to plug in a USB webcam. However, the CPU usage of the machine rises to about ~90% while using applications like Skype or Photobooth.

Can anyone shed some light on why this is happening/why firewire is uses less CPU usage? Thanks.
 

Zotaccian

macrumors 6502a
Apr 25, 2012
645
7
USB requires CPU to control the bus and data transfer while Firewire does it by itself. Getting a FireWire webcam will free CPU resources to other tasks so you could consider getting iSight or compatible, if there is one.
 

cocacolakid

macrumors 65816
Dec 18, 2010
1,108
20
Chicago
If you're in the U.S., keep an eye on your local Craigslist, if you have one. I see iSight camera's pop up there occasionally for cheap (cheaper than eBay).
 

skateny

macrumors 6502
Jul 19, 2012
448
0
New York, NY
So my Powerbook G4 12" has 2 USB 2.0 ports, and I used one of them to plug in a USB webcam. However, the CPU usage of the machine rises to about ~90% while using applications like Skype or Photobooth.

Can anyone shed some light on why this is happening/why firewire is uses less CPU usage? Thanks.

This is not mine, nor do I have any personal interest in its sale:

http://newyork.craigslist.org/mnh/sys/3514579026.html
 

DarkSel

macrumors 6502
Original poster
Dec 22, 2012
278
81
USB requires CPU to control the bus and data transfer while Firewire does it by itself. Getting a FireWire webcam will free CPU resources to other tasks so you could consider getting iSight or compatible, if there is one.

So why is this a problem specifically with PowerPCs? I have a single core mobile Celeron running Windows XP that handles a USB webcam with minimal CPU usage.
 

Zotaccian

macrumors 6502a
Apr 25, 2012
645
7
G4 is not fast cpu, you did not say what model you have but still. Also what is the Celeron model you are comparing to? Optimizations are of course another factor, prime example where Windows -version of a software works much better is Adobe Flash.
 

eyoungren

macrumors Penryn
Aug 31, 2011
28,775
26,843
I got mine at a university surplus sale. $20, almost unused.
I got my iSight, $50 off eBay. The seller got it the same way you did. University surplus. Didn't get all the stuff with it, except for the laptop mount and had to go buy a thin firewire cable, but my iSight rocks.

This was over a year ago, BTW.

OP, it's down to drivers and how they interact with the CPU. I had an Icecam from Macally. It sucks, which is why I got an iSight.

There is software out there that will let you use iChat with USB which supposedly lessens the CPU hit, but I don't use iChat for video. I'd have to go look it up. All the way around though, USB cams for PowerPC laptops just suck.
 

Zotaccian

macrumors 6502a
Apr 25, 2012
645
7
Here's the model: http://ark.intel.com/products/27172/Intel-Celeron-Processor-1_70-GHz-128K-Cache-400-MHz-FSB

The bus speed is 400 MHz, significantly faster than the G4. I'd guess this plays some part.

Yes, G4 has/had poor FSB compared to what Intel and AMD had. The link you gave is for desktop Celeron, there are laptops which use desktop processors, but are you sure it is that and not Celeron M running at 1.73ghz when it could based on Intel's "Yonah" core which Core Duo -processors use, there was also newer Celeron M at 1.73ghz.

Edit: and it seems that there was also Celeron M at 1.7ghz which indeed had 400mhz but 1mb cache. The reason why I ask is that netburst -based desktop Celerons like the one you linked should have awful performance... but maybe video streaming is ok for them, netburst and Pentium 4 were designed as media-cpu's with high FSB bandwidth
 

DarkSel

macrumors 6502
Original poster
Dec 22, 2012
278
81
Yes, G4 has/had poor FSB compared to what Intel and AMD had. The link you gave is for desktop Celeron, there are laptops which use desktop processors, but are you sure it is that and not Celeron M running at 1.73ghz when it could based on Intel's "Yonah" core which Core Duo -processors use, there was also newer Celeron M at 1.73ghz.

Whoops, here's the mobile version of that processor: http://ark.intel.com/products/27147/Intel-Celeron-M-Processor-390-1M-Cache-1_70-GHz-400-MHz-FSB
 

Zotaccian

macrumors 6502a
Apr 25, 2012
645
7

Okay, so it might be that the CPU and software optimizations are simply better in your Windows -laptop. Here is Celeron M 380 runs 100mgz slower than your 390

http://browser.primatelabs.com/geekbench2/1443398

If you have the fastest 12" PB you have 1.5 Ghz G4 which scores 725 at Geekbench as reported by Everymac.com so atleast in this theoretical test Celeron M with Dothan core is indeed faster.

----------

[/quote]
 

DarkSel

macrumors 6502
Original poster
Dec 22, 2012
278
81
Okay, so it might be that the CPU and software optimizations are simply better in your Windows -laptop. Here is Celeron M 380 runs 100mgz slower than your 390

http://browser.primatelabs.com/geekbench2/1443398

If you have the fastest 12" PB you have 1.5 Ghz G4 which scores 725 at Geekbench as reported by Everymac.com so atleast in this theoretical test Celeron M with Dothan core is indeed faster.

----------


I guess that's not too much of a surprise. The M 390 was released in December 2005, while the PB G4 12" was released in January 2005. I wish Apple would provide proper USB support for the Powerbooks :/
 

cocacolakid

macrumors 65816
Dec 18, 2010
1,108
20
Chicago
I wish Apple would provide proper USB support for the Powerbooks :/


In a way, they did, the iSight camera works better than any USB camera ever did. I know it's Firewire, but they engineered the best camera they could at the time. And when you consider that the iSight camera's were released 10 years ago, it's amazing the picture quality they still give compared to many of today's add-on webcam's (yes you can buy a nicer one, but you SHOULD be able to buy a nicer one 10 years after the fact anyway).
 

Zotaccian

macrumors 6502a
Apr 25, 2012
645
7
I guess that's not too much of a surprise. The M 390 was released in December 2005, while the PB G4 12" was released in January 2005. I wish Apple would provide proper USB support for the Powerbooks :/

First Dothans were launched in 2004, Celeron is course the low wend CPU for Intel. 1.7GHz Pentium M 735 would have been evwen faster with its 2MB L2 cache. G4 was just too old technology, but it might still be optimizations with the OS, Skype and camera drivers which play huge factor. However, getting a Fw camera should improve the situation, get iSight which should have thwe best driver support for OS X, should be compatible with Skype, woyld be strange if not.
 

cocacolakid

macrumors 65816
Dec 18, 2010
1,108
20
Chicago
I got mine at a university surplus sale. $20, almost unused.

That's a nice price. I see them on eBay go for $60-100 or so pretty regularly, or did last time I checked a few months ago.

I see them once in a while on the Chicago CL for as low as $25, but normally $50 or less.

UPDATE: It looks like you can get one for $30+ on eBay these days, with a handful in good working condition for $30-40.
 
Last edited:

DarkSel

macrumors 6502
Original poster
Dec 22, 2012
278
81
First Dothans were launched in 2004, Celeron is course the low wend CPU for Intel. 1.7GHz Pentium M 735 would have been evwen faster with its 2MB L2 cache. G4 was just too old technology, but it might still be optimizations with the OS, Skype and camera drivers which play huge factor. However, getting a Fw camera should improve the situation, get iSight which should have thwe best driver support for OS X, should be compatible with Skype, woyld be strange if not.

That's a shame :/

I thought the G4 was superior to the Pentium 4, but now it seems that it's even worse than a Celeron.
 

cocacolakid

macrumors 65816
Dec 18, 2010
1,108
20
Chicago
That's a shame :/

I thought the G4 was superior to the Pentium 4, but now it seems that it's even worse than a Celeron.

I wouldn't say that. You've stumbled upon one of the limiting factors of older technology. But it's not like Celeron's or even P4's are good choices anymore. A G4 can be a nice budget computer or second computer/kids computer/hobby computer, etc.

They're all at least 7 years old. How many 7 year old Windows laptops are still working and of any real ability? I know XP can still run on those older CPU's no problem, and there are more compatible programs, but the old Windows hardware wouldn't be in my top 10 choices, where many of the old G4 Macs are still cool and worthwhile. You just have to know and accept the limits they have. And webcams are one of the limits.

If you really need to use a webcam, then definitely get an iSight. You'll also leave one of your USB ports open.
 

DarkSel

macrumors 6502
Original poster
Dec 22, 2012
278
81
I wouldn't say that. You've stumbled upon one of the limiting factors of older technology. But it's not like Celeron's or even P4's are good choices anymore. A G4 can be a nice budget computer or second computer/kids computer/hobby computer, etc.

They're all at least 7 years old. How many 7 year old Windows laptops are still working and of any real ability? I know XP can still run on those older CPU's no problem, and there are more compatible programs, but the old Windows hardware wouldn't be in my top 10 choices, where many of the old G4 Macs are still cool and worthwhile. You just have to know and accept the limits they have. And webcams are one of the limits.

If you really need to use a webcam, then definitely get an iSight. You'll also leave one of your USB ports open.

I wouldn't say that :p

I have a Pentium 4 @ 3.2 GHz powering my home server.

But yeah, I understand your point. I already have an Ultrabook with more than enough processing capability, I was more curious about the limitations of the G4, and now I'm enlightened.

Thanks for the advice guys.
 

Zotaccian

macrumors 6502a
Apr 25, 2012
645
7
I wouldn't say that. You've stumbled upon one of the limiting factors of older technology. But it's not like Celeron's or even P4's are good choices anymore. A G4 can be a nice budget computer or second computer/kids computer/hobby computer, etc.

They're all at least 7 years old. How many 7 year old Windows laptops are still working and of any real ability? I know XP can still run on those older CPU's no problem, and there are more compatible programs, but the old Windows hardware wouldn't be in my top 10 choices, where many of the old G4 Macs are still cool and worthwhile. You just have to know and accept the limits they have. And webcams are one of the limits.

If you really need to use a webcam, then definitely get an iSight. You'll also leave one of your USB ports open.

In fact I think there are many 7 year old Windows laptops fully working and still running supported OS with the ability to even upgrade to Windows 7 (atleast some of them, the GPU driver support is usually the problem). The difference between Macs and PCs are that the are several PC manufacturers and many many many models, PCs do not hold value so temptation to just sell or throw fully working machine to trash bin is much higher than with Macs. Especially with the old Macs the design is however still great and was light years ahead what the PC side had to offer in it's time and I myself buy old PPC Macs now and then because they are something different. However I still think that if the performance and software support is the key thing those machines are not the best, Pentium M laptop with Windows XP fares better in that area.
 

cyberghoser1

macrumors member
Nov 18, 2009
98
0
Athens, Hellas
In fact I think there are many 7 year old Windows laptops fully working and still running supported OS with the ability to even upgrade to Windows 7 (atleast some of them, the GPU driver support is usually the problem). The difference between Macs and PCs are that the are several PC manufacturers and many many many models, PCs do not hold value so temptation to just sell or throw fully working machine to trash bin is much higher than with Macs. Especially with the old Macs the design is however still great and was light years ahead what the PC side had to offer in it's time and I myself buy old PPC Macs now and then because they are something different. However I still think that if the performance and software support is the key thing those machines are not the best, Pentium M laptop with Windows XP fares better in that area.

I agree with you, i've spent few days ago 238$ for a powerbook G4, hopefuly the latest model from apple back that time. I would never imagine myself spend such money on a old P4 or Celeron laptop with windows, a mac is a mac, i've seen that before with my iBook 800MHz and now with the powerbook, God, those macs never die, 7 and almost 8 years machine and still runs fine, i can watch videos/movies surf the web, lot of browser choices to match current website's new technologies etc.. Of course its old hardware/software, but its not MS Crap, it just works :)
 

blesscheese

macrumors 6502a
Apr 3, 2010
698
178
Central CA
So my Powerbook G4 12" has 2 USB 2.0 ports, and I used one of them to plug in a USB webcam. However, the CPU usage of the machine rises to about ~90% while using applications like Skype or Photobooth.

Can anyone shed some light on why this is happening/why firewire is uses less CPU usage? Thanks.

I haven't used Skype in a while with my PPC, but with my Intel MBA, it *sucks* power and drives the CPU temps up.

The other comments about the USB disadvantages vs. Firewire are also correct.
 

PowerPCMacMan

macrumors 6502a
Jul 17, 2012
800
1
PowerPC land
G4 and G5?

Sorry if I am joining this discussion a bit too late, but didn't the G5 compare favorably with the Pentium IV processor where as the G4 compared to that of the late Pentium III and early Pentium IVs?

Lets take a few examples:

The Highest processor based Power Mac G4 - Mirror Drive Door/FW800 running at dual 1.25 ghz PowerPC G4 7455 with 167mhz bus, and also the Dual 1.42. Both these processors included 2MB L3 Cache per processor, some earlier models only included 1MB L3 Cache - Wasn't this to compensate for the slow FSB of the G4?

Next, the PowerBook G4 Dual-layer 1.67ghz with its 167mhz bus.. the problem here is that the 7447A/B lacked L3 Cache. Its quite ironic that the later Titanium PowerBooks offered L3 Cache.. but would there compensation using the L3 make them much faster than the 2006 1.67 PowerBook G4?

Finally, the Dual Core G5s, and Quad G5. The Quad uses 4 X 2.5Ghz PowerPC G5 970MP(2 Processors and 2 cores), has a FSB of 1.25Ghz with NO L3 Cache. I guess the impressive FSB of 1.25 on the Quad is why L3 never made it on the G5 line. Dual Core 2.3 and 2.0 have 1.0Ghz FSB and no L3 either.

I think the G5 Quad and Dual Core are close to or on par with the latest to LAST Pentium IV machines. I can also include maybe the early Core Duo or Core Solo machines.. maybe lower clock speed Core2Duo machines.

But, really at the end of the day, depending on usage, neither machine is faster than the other. The only way to see which is faster is based on types of software applications. Rendering and video encoding on the G5 is much faster than on the Pentium IV machines - for instance.

Sorry if this is somewhat wordy, just that I wanted to know where the G5 and G4 fall in terms of comparative equivalency to the Pentium III, IV and later Core Duo processors.
 

ybz90

macrumors 6502a
Jul 10, 2009
609
2
Sorry if I am joining this discussion a bit too late, but didn't the G5 compare favorably with the Pentium IV processor where as the G4 compared to that of the late Pentium III and early Pentium IVs?

Lets take a few examples:

The Highest processor based Power Mac G4 - Mirror Drive Door/FW800 running at dual 1.25 ghz PowerPC G4 7455 with 167mhz bus, and also the Dual 1.42. Both these processors included 2MB L3 Cache per processor, some earlier models only included 1MB L3 Cache - Wasn't this to compensate for the slow FSB of the G4?

Next, the PowerBook G4 Dual-layer 1.67ghz with its 167mhz bus.. the problem here is that the 7447A/B lacked L3 Cache. Its quite ironic that the later Titanium PowerBooks offered L3 Cache.. but would there compensation using the L3 make them much faster than the 2006 1.67 PowerBook G4?

Finally, the Dual Core G5s, and Quad G5. The Quad uses 4 X 2.5Ghz PowerPC G5 970MP(2 Processors and 2 cores), has a FSB of 1.25Ghz with NO L3 Cache. I guess the impressive FSB of 1.25 on the Quad is why L3 never made it on the G5 line. Dual Core 2.3 and 2.0 have 1.0Ghz FSB and no L3 either.

I think the G5 Quad and Dual Core are close to or on par with the latest to LAST Pentium IV machines. I can also include maybe the early Core Duo or Core Solo machines.. maybe lower clock speed Core2Duo machines.

But, really at the end of the day, depending on usage, neither machine is faster than the other. The only way to see which is faster is based on types of software applications. Rendering and video encoding on the G5 is much faster than on the Pentium IV machines - for instance.

Sorry if this is somewhat wordy, just that I wanted to know where the G5 and G4 fall in terms of comparative equivalency to the Pentium III, IV and later Core Duo processors.

I'm fairly certain that the G4 outperformed the P4. As you mention of course, "performance" is dependent upon the optimization of software for the particular chip. That said, when the G4 was first introduced, it was said to be at least on par or far exceeding the speeds of the fastest x86 chips.

By the time the last G4 computer was introduced however, the chip, even after refreshes and revisions, was showing its age, and probably less than half as powerful as the Core Solo mobile processors that replaced them. I'm not an expert on this particular topic, but I recall reading about a redesign of the G5, called Powerficient by PA Semi (later snapped up by Apple anyway to build iPhone chips), that lowered temperatures and raised clock speeds to levels that were competitive with Intel. Unfortunately, it was just too little, too late.

I'm actually using my rebuilt PowerBook right now. Something that amazes me still is how the fans haven't even turned on. Passive cooling would never work on a modern x86-based mobile device.

Back on topic, out of curiosity, is the Agere chip in the PowerBook G4 the firewire controller? I noticed it when I was replacing the heatsink/fans.
 
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