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Quartz Extreme Burdens CPU and Slows System?

skel_73

skel_73

macrumors member
Original poster
Feb 12, 2002
38
18
Toronto
Greetings all,

I'm sure there are some of you out there in the 'technical know' that could shed some light on this.

It's my understanding that Quartz Extreme is meant to alleviate processor load and make everything feel a little more 'snappy'.

My laptop is the 1.33Mhz 17" running the latest Tiger. I find it a little sluggish, but it's ok (all things being relative).

At home I have an old AGP 400 Mhz G4, for which I swapped in a 1.2 Ghz G4 upgrade card from OWC.

Here's the thing. It feels speedier than my more modern laptop with the faster processor.

Why could that be?

We the other day I checked widgets on my old APG workhorse and discovered that when opening a widget, there is no 'ripple' effect. That must mean that Quartz Extreme is not able to run on that computer.

So what I'm asking is, for all it's eye candy splendour, does Quartx Extreme tax the CPU. Because my old AGP is way snappier in Tiger than my faster laptop and that's the only difference I can see.

Tell me if you think I'm out to lunch........
 
skel_73 said:
Greetings all,

I'm sure there are some of you out there in the 'technical know' that could shed some light on this.

It's my understanding that Quartz Extreme is meant to alleviate processor load and make everything feel a little more 'snappy'.

My laptop is the 1.33Mhz 17" running the latest Tiger. I find it a little sluggish, but it's ok (all things being relative).

At home I have an old AGP 400 Mhz G4, for which I swapped in a 1.2 Ghz G4 upgrade card from OWC.

Here's the thing. It feels speedier than my more modern laptop with the faster processor.

Why could that be?

We the other day I checked widgets on my old APG workhorse and discovered that when opening a widget, there is no 'ripple' effect. That must mean that Quartz Extreme is not able to run on that computer.

So what I'm asking is, for all it's eye candy splendour, does Quartx Extreme tax the CPU. Because my old AGP is way snappier in Tiger than my faster laptop and that's the only difference I can see.

Tell me if you think I'm out to lunch........
Click to expand...


Hm... A GPU can be Quartz Extreme compatible, but not Core Image (new Tiger feature) capible. Your 17" PB should be both. The APG may or may not be, depending on the video card in it. It could very well be that the extra Core Image features are slowing your PBook down, but since your desktop isn't able to display those features, it skips them and you see an improvement in performance.

I noticed on my iMac G5 RevA that although the 5200 was Core Image compatible, the effects it performed slowed my system down when compared to 10.3.9. If I had kept the machine I would have looked for a way to disable them.

That doesn't really answer your question, but at least I can confirm that it seemed that Core Image effects in Tiger slowed my system down even though, in theory, it should have been able to handle them.
 
The ripple effect is Core Image, not Quartz Extreme. The processor is forced to make up for some of the lack of a Core Image supported video card, but it shouldn't make a huge difference in processor performance. With a Core Image enabled video card, you would see a significant boost in video speed and smoothness. I'll let you know how big the difference is with the CPU, since i have a Radeon 9800 Pro coming today. :)
 
Both machines are running the current version of Tiger.

Specwise:

The OWC 1.2 Ghz G4 in an APG 400Mhz System:

OS: Latest Tiger
System Bus: 100 Mhz
Processor: OWC 1.2 Ghz w/ 2MB L3 cache
RAM: 1.2 Gigs
Video: RADEON 9600 PRO 4X AGP 64MB
HD: 7200 RPM 80 Gig

Powerbook:

OS: Latest Tiger
System Bus: 167 Mhz
Processor: 1.33 Ghz w/ 512 L2 cache
RAM: 1.2 Gigs
Video: stock 64MB
HD: 5400 RPM 80 Gig

So looking at these specs - where the Powerbook clearly has the edge in most areas - the souped up AGP G4 is so much faster because of the HD rotation speed (sorry, but the difference is drastic and has been notes in cases that don't involve reading from or writing to the HD). The 2MB L3 cache on the upgrade card is enough to overcome all the other technical inferiorities?? Quartz Extreme not being used is the only major difference I can think of.......

And what is the point of Core Video if it taxes the system so much for what in return.... a cool looking ripple effect.... there must be something else going on here......
 
Yes and this goes to my point that theoretically if my PowerBook did not have Core Image capability it would be appropriately faster than my old G4, instead of quite a bit slower.... and if that's the case.... why the handicap? For a ripple effect?
 
skel_73 said:
Yes and this goes to my point that theoretically if my PowerBook did not have Core Image capability it would be appropriately faster than my old G4, instead of quite a bit slower.... and if that's the case.... why the handicap? For a ripple effect?
Click to expand...
It shouldn't be slower than your Power Mac. I would suspect something else is wrong. Like I said, I'll tell you how the speed difference is when my 9800 gets here.
 
drlunanerd said:
Uh? Apple say it is: http://www.apple.com/macosx/features/coreimage/
Click to expand...
Hmm, interesting. My dad was looking at purchasing an eMac (which ship with the 9600) a few weeks ago, and he wanted to know if it supported Core Image. I looked at the requirements then, and it said 9600 XT, but not the regular 9600. Very interesting. So, it should support CI, but it doesn't. This is becoming more complicated......
 
A couple of other things that I noticed:
The Power Mac has a 2 MB L3 cache and a 7200 RPM HD
The PowerBook has no L3 cache and a 5400 RPM HD

Bothe of these factors are probably the difference that you are feeling. Still not sure why the 9600 doesn't support CI......
 
I'm thinking back and I don't remember the exact reason, but Apple had a technical justification for not using a big L2 cache in the modern Powerbook. But if the cache is the main culprit here, how can they justify not putting a larger L2/L3 cache in the top line pro portable??

Regardless, when I see the huge performance difference - the old AGP feels like a much faster machine, maybe 35% faster based on feel - it seems odd that the lack of Core Image in the upgraded AGP has NOTHING to do with it?

Another way of phrasing the question:

Does Core Image cause performance hits?
 
skel_73 said:
Does Core Image cause performance hits?
Click to expand...
Since I don't have a Core Image Mac as of yet, I don't know. I will be able to tell you once I get the 9800 installed. I'm on this G4 all the time, and I will be able to detect the slightest performance increase/decrease with CI.
 
dsharits said:
A couple of other things that I noticed:
The Power Mac has a 2 MB L3 cache and a 7200 RPM HD
The PowerBook has no L3 cache and a 5400 RPM HD

Bothe of these factors are probably the difference that you are feeling. Still not sure why the 9600 doesn't support CI......
Click to expand...

The Radeon Mobility 9600 is not the same as the Radeon 9600 found in desktops. The desktop 9600 XT is just a slightly higher clocked version of the 9600, feature whise the two are identical hence the reason both support core image.

As for whether the Mobility 9600 supports core image some say it does. A simple way to check is to look in the 'about my mac' under graphics cards and see if it says 'yes' next to 'core image support'. I've included a snap of my 17in 1.67GHz as you can see it does support 'core image'
 

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BTW the L3 cache makes a massive difference on G4 CPUs. I can back up what's being said here - I have a 1.4GHz upgrade card with 2MB L3 and it's really snappy - feels faster than a new 1.67GHz Powerbook 17".

However I'd love to know what's going on with the 9600 on your PowerMac. Can you check System Profiler and confirm under Graphics/Displays that it says "Core Image: Not Supported" and that you do have a 9600 (think it will say ATY,RV350 for Chipset Model).
 
I will verify the card when I am back home. I'm 98% sure.

Whether it's capable or not, the fact is it seems Core Image is not running and this cpmputer has a MUCH snappier GUI than the laptop with the better specs.

BTW, at my office, where I am now, I am on a G5 iMac which obviously has Core Image, and in terms of GUI 'snapiness' it's on a level with my souped up no-core-image AGP G4. I wonder if it would be significantly faster with no Core Image?

I also have a dual 2.0 G5 here and that one is very snappy. Perhaps one needs a truly kick-ass G5 to smoothly power Core Image???
 
I dunno about the rest of you but Core Image and Tiger run just as fine on my powerbook as they do on our school's G5s. I've never noticed a slowdown of any kind.
 
Maybe it can all be attributed to the L3 cache on the OWC upgrade card in the old G4.
 
The 9600 does support Core Image, 100% guaranteed.

It's not a matter of if Apple 'certifies' it, but of the cards capabilities. A card that supports Pixel Shader 2.0 will support CoreImage, and the 9600 and up does this. (Actually, 9500 and up, but who runs a Mac with one of those ;) )
 
My bad, folks.

I am home now and the graphics card is a GeForce4 MX 32MB card, which obviously does not support Core Image.

However it does make my souped up AGP G4 *even worse* on specs, which makes the fact that it seems 35% faster than the much better outfitted (spec-wise) laptop even harder to understand.

I'm not kidding, noticably fewer bounces, less beachballs, programs opening more quickly, snappier windows etc. etc.

However today I took the plunge and ordered a dual 2.7 G5 to replace the souped-up AGP G4 in my home recording studio. Quite pumped about that.
 
Okay, first of all, which model of the Power Mac G4 do you have? AGP graphics you said? Which would technically be the code-named Sawtooth Power Mac G4. This model only support 2X AGP, not 4X. Maybe that's why Core Image is not supported. If you can, it would be nice if we did have a snapshot of your System Profile. :)

And if I recall, certain models of PowerBooks have bugs with Core Image. I have a rev. a PowerBook G4 1 Ghz, and my brother has a Sawtooth Power Mac G4 with a Sonnet 1 Ghz Upgraded CPU. He has a Radeon 9600 Pro running at 2X AGP and I have a Mobility Radeon 9600 running at 4X AGP. My computer whoops his ass in every way, especially with Core Image. So like I said, there might be a bug with certain PowerBooks.
 
if you do not have a core image supported video card then that load is passed off to the cpu. apple claims this doesn't really slow things down much. you lose the ripple effect but who cares? eye candy is a burden to performance.
 
It's a little funny; Apple's site doesn't list the mobility 9600 in my dad's powerbook as core compatible, but it is. Anyway, I thought I'd post that I experienced some speed issues similar to Skel, my Powerbook G4 400 (384MB PC100, 8MB rage m3) was much snappier running Panther than my dad's 1 Ghz Powerbook (768MB DDR, 64MB Radeon Mobility 9600), but of course his book smoked mine in every application other than just the OS. I should note that I had a 5400 rpm hard drive in my book, but so did my dad.
 
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