I am actually MORE confused now, because the GS we have on our 2008 iMacs has 512Mb...this doesn't match with NVIDIA's info.
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Snow Leopard H.264 Hardware Acceleration and OpenCL Requirements
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I am actually MORE confused now, because the GS we have on our 2008 iMacs has 512Mb...this doesn't match with NVIDIA's info.
That's because the Mac edition of the 8800GS is actually a 8800GTS.
underclocked of course.
That's because you have a mobile card, not a desktop one. Apple likes to relabel video cards in strange ways. Its an 8800m GTS.
Yes, and that would involve adding expense and noise to a machine for purely theoretical reasons.
I suspect quite the opposite occurred. I suspect that Apple designed to a predicted thermal envelope, then during testing discovered that it got too hot. Then, *after testing*, they underclocked the graphics to avoid the problem.
I also seem to remember at least one case where Apple slowed the GPU clock even more in a firmware update to "fix" a problem in the field.
I stand by my firm belief that it is possible that my speculation is somewhat related to the facts.
I also believe in the rule that with computer hardware and software things which aren't tested do not work. Apple's laptops and laptops-on-sticks have a history of heat-related issues running previous applications. I don't find it unreasonable to have suspicions that OpenCL and H.264 acceleration could be a problem.
(below)
The point is that usually things which aren't tested do not work.
OpenCL and encoding would definitely involve streaming multiple threads of work to the GPU for extended lengths of time.
Decoding would be fairly simple compared to encoding - Windows has been using hardware assisted decoding for years without any noticeable issues.
Let me repeat again that I'm merely speculating that the new features may cause some models to go outside their thermal design envelope, and Apple may have decided to exclude them from the "supported" list even though the chips are capable.
I'm ending the back-and-forth on this topic, no point to drag it out more. (But I'll bookmark this thread just in case after 10.6 ships there are reports of overheating Macs
)OK...found this, which seems to settle the issue: it's a 8800M GTS (the mobile version of the GTS).
https://forums.macrumors.com/threads/493628/
Bottomline: yes, our iMacs are compatible with OpenCL.
Whats this? Apple using new software features to make users upgrade their hardware? Sounds like something Microsoft would do
I just bought my MBP in early October (8600M GT). The computer is only 8 months old and there's no indicated support for hardware acceleration of graphics on it under Snow Leopard. Unbelievable. Maybe Windows7 will have better support for Apple's hardware than Apple....
OpenCL and h.264 decoding are a problem but gaming or encoding isn't?
The 8800M GTS isn't really a mobile version of the 8800GTS (G80 or G92).
There isn't really a good desktop comparison but the closest would be an underclocked 9600GT.
There was a long thread about the exact same question a few months ago, and the story from serious h.264 developers is that h.264 is very difficult to accelerate using graphics hardware, that the 5 times improvements come from an encoder that isn't nowhere near the quality of what you expect, and that while it is relatively easy to make a rubbish encoder 5 times faster, a good encoder needs a lot of cleverness that is very, very hard indeed to accelerate.
OpenCL will do wonders for some people who do High Performance Computing; the kind of people who'd want a MacPro with integrated graphics and four high end graphics cards for computations; it will do a lot less for h.264 encoding.
Dave, your point is excellent. My macbook is great for what I need. Even at $29 I'm not thinking that 10.6 would be worth the upgrade if my video card isn't supported (at least for openCL). After all, it seems like even with a complete erase and install that OS 10.x.4 needs to roll around before the bugs are out. Without an upgrade in functionality, it's not worth even $29 to have trouble with my otherwise perfect machine currently running 10.5.7.
Until I see a demo of OpenCL doing anything special I'll consider it a neat technology in theory.
Video encoding IMO is best done with CPU grunt or grab something like a Matrox MXO if you can.
Video encoding IMO is best done with CPU grunt or grab something like a Matrox MXO if you can.
Hardware acceleration doesn´t mean encoding support, but decoding solely. My check was pretty simple: Before I couldn´t play any 1080p trailers without doing nothing else on the machine. Now I can do it - and do many other things at the same time. In numbers: Before hardware acceleration my CPU peaked at around 90% to full 100% playing 1080p without anything else running in the background, now it´s around 30% to 60% (mostly depending on heavy moving scenery). That´s a huge difference only acceleration can deliver - my machine hasn´t changed a bit in between this extreme shift of performance.
Nvidia´s specs are pretty clear on this: http://www.nvidia.com/object/7_series_techspecs.html It´s called "PureVideo". ATI got the same technology bundle centered around hardware acceleration of video content is called "Avivo": http://ati.amd.com/products/radeonx1900/specs.html
So the most of the graphics hardware from the last three years supports it. Basically it´s just a driver issue, therefore Apple´s corner to simply activate it. I don´t believe it´s a heat saving strategy regarding Apples notebooks, as letting the CPU do the full decoding causes much more heat stress on the system than using additional power from the GPU.
http://www.apple.com/macosx/specs.html
Apple's website will answer nearly all your questions. Always look there first.
I can't speak to H.264, but I find it interesting that only GPUs supporting AMD's Stream and nVidia's CUDA are on Apple's OpenCL list. It's possible this has nothing to do with Apple and everything to do with what AMD and nVidia will support. I find it incredibly hard to believe Apple is doing anything more than porting (and testing) AMD's and nVidia's OpenCL software into Mac OS X.
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Well, I think thats stretching it-nobody has a gun at their head to buy SL
A lot of the "I need to own it the day BEFORE release" anxious types may be bothered BUT
who says these are final specs?
who says 10.6.2 wont open up new card support
Many of you dont really need the performance upgrades being offered
anyway-look how MS nearly yanked XP away from people
interesting
just reading Bloomberg that Balmer has threatened to outsource most of MS to India if they are taxed on overseas sales.
Now there is a real patriotic guy
spit on him
http://www.bloomberg.com/apps/news?pid=20601087&sid=aAKluP7yIwJY
http://www.computerweekly.com/Artic...to-move-microsoft-jobs-out-of-us-over-tax.htm
jeezus-they toss billions out the window on Zoon-but paying taxes make them want to seek revenge on a growing unemployed IT workforce here in the US effectively holding them hostage??
The spec page only mentions the 9400M nvidia chip for h.264 hardware acceleration.
The question was raised before but I didn't see a reply: Does that mean that if I switch over to using the 9600M GT GPU the macbook pro _can't_ do h.264 hardware acceleration?
The MacBook Pro already uses the 9400M for h.264 hardware acceleration. Regardless if you're using the IGP or discrete graphics.
Ah, I was under the impression that it used one gpu or the other, not both at the same time. Do you have a link where I can read about this?
No it can't be. According to the sometimes reliable wikipedia...
On April 28 2008, Apple announced an updated iMac line featuring an 8800 GS. However, the GPU is actually a rebranded NVIDIA GeForce 8800M GTS.
The real 8800 GS is a desktop chip with a higher power draw, lower RAM ceiling, narrower bus, etc.
So I'm convinced the 2008 iMac with the so-called 8800 GS is supported.
I just ordered a 24" iMac that is being delivered tomorrow. Are they seriously telling me that my 2.8 Ghz iMac with a Radeon 2600 can't do open CL, even though it clearly bests the 9400m in performance? Not happy.