What GPU would a 5K iMac likely have?

[Mago]

1st there is no 5K iMac, not practical now, maybe for 2016.

2n Yosemite includes drivers for nVidia 9xx, thus unlikely Apple introduced drivers for an unplanned products.
3rd the retina iMac sure will come at 4k resolution this don't require thermal redesign neither an ultra expensive panel, and this retina iMac can be built at the same cost as last year model.

Thus no sense to deliver an retina 5K iMac with sub par performance or huge and expensive redesign to handle dual GPU and 6 core cpu, as high end device the 27" iMac isn't something the users buy to surf the Web, so an poorly implementation it's unlikely, while now it's possible to deliver an 4k iMac 27 with optimal implementation of cpu and gpu.

The argument on double pixel easy transition to retina quality, lacks of knowledge on how OSX render text and Windows (it's natively resolution and dpi independent), this also was optimized from Mavericks and now on Yosemite it's very mature, so you can adapt the dpi and gui to match any screen dpi, not just *doubling*, since it's optimal at any dpi.

 

[Irishman]

The rumours suggest a move to AMD but what are your guesses?

Something custom made.

 

[Lava Lamp Freak]

1st there is no 5K iMac, not practical now, maybe for 2016.

2n Yosemite includes drivers for nVidia 9xx, thus unlikely Apple introduced drivers for an unplanned products.
3rd the retina iMac sure will come at 4k resolution this don't require thermal redesign neither an ultra expensive panel, and this retina iMac can be built at the same cost as last year model.

Thus no sense to deliver an retina 5K iMac with sub par performance or huge and expensive redesign to handle dual GPU and 6 core cpu, as high end device the 27" iMac isn't something the users buy to surf the Web, so an poorly implementation it's unlikely, while now it's possible to deliver an 4k iMac 27 with optimal implementation of cpu and gpu.

The argument on double pixel easy transition to retina quality, lacks of knowledge on how OSX render text and Windows (it's natively resolution and dpi independent), this also was optimized from Mavericks and now on Yosemite it's very mature, so you can adapt the dpi and gui to match any screen dpi, not just *doubling*, since it's optimal at any dpi.

As I posted in the other thread, nothing has changed with how HiDPI works in Yosemite. It is still not true resolution independence. It just doubles and then scales to the native display resolution if you aren't using the "Best (Retina)" option. That results in a slightly fuzzy image.

So, a 5k iMac would have no more stress on the GPU than a 4k iMac.

 

[Mago]

As I posted in the other thread, nothing has changed with how HiDPI works in Yosemite. It is still not true resolution independence. It just doubles and then scales to the native display resolution if you aren't using the "Best (Retina)" option. That results in a slightly fuzzy image.

So, a 5k iMac would have no more stress on the GPU than a 4k iMac.

No you still outdated, this is pixel doubling, an previous implementation of retina display, on Yosemite GUI elements for 27" retina display will be scale relatively to the screen size not the resolution, so an font measuring 1/8“ on 3k resolution will measure 1/8" on 4k resolution, you can also setup the display to shown the same GUI elements at 1/6" on 4K and if you switch (or have another display) connected) with HD resolution the same font or GUI element will be show measuring 1/6", if you need double desktop space, you should setup the GUI to decrease object size, so the actual resolution has nothing to do with the size of the GUI elements, no scaling need since everything is drawn according screen size not resolution.

 

[Lava Lamp Freak]

No you still outdated, this is pixel doubling, an previous implementation of retina display, on Yosemite GUI elements for 27" retina display will be scale relatively to the screen size not the resolution, so an font measuring 1/8“ on 3k resolution will measure 1/8" on 4k resolution, you can also setup the display to shown the same GUI elements at 1/6" on 4K and if you switch (or have another display) connected) with HD resolution the same font or GUI element will be show measuring 1/6", if you need double desktop space, you should setup the GUI to decrease object size, so the actual resolution has nothing to do with the size of the GUI elements, no scaling need since everything is drawn according screen size not resolution.

I think we're talking about two different things. I'm not familiar with what options developers have available to them. I'm referring to how the OS renders the UI when you use a scaled resolution. Yosemite still renders the same as Mavericks. If you choose any resolution other than "Best (Retina)" it is still scaling and it is still slightly fuzzy because of it.

My point is that it doesn't matter if the iMac has a 4k display or a 5k display. It is the same to the GPU either way because even on the 4k screen it is still having to render at 5k and then downscale to 4k. It still does this in Yosemite.

Edit: If you are claiming that a 4k 27-inch iMac would have a UI that is equivalent to 2560x1440 without any downscaling neccessary, then please provide some documentation or evidence that Yosemite is designed to do this.

 

[yoak]

I would love an iMac with a 5K screen, but it would have to be able to handle my 5K RED footage as well, at least in playback.
Doubt that will happen though, I could live with half res playback, and still see the full res image when paused

 

[Mago]

I think we're talking about two different things. I'm not familiar with what options developers have available to them. I'm referring to how the OS renders the UI when you use a scaled resolution. Yosemite still renders the same as Mavericks. If you choose any resolution other than "Best (Retina)" it is still scaling and it is still slightly fuzzy because of it.

No, this is for legacy apps, from lyon apps can be resolution independent (just as new iOS apps) so an guí element at same scree size will have the same relative real stare or foot print, despite if 1K,2K,4,8K of course as higher the resolution smoothest the lines.

My point is that it doesn't matter if the iMac has a 4k display or a 5k display. It is the same to the GPU either way because even on the 4k screen it is still having to render at 5k and then downscale to 4k. It still does this in Yosemite.

No, displaying the same GUI element on 5K will require to render double the pixels, no scaling is done since everything is directly rendered on target resolution. This happened to legacy non retina optimized apps, also for pseudo optimized apps, native resolution independent apps show guí elements the same size independent the actual resolution or screen size, am good example it's Safari, compare it against ms word (non 360), also Web pages are natively rendered on target screen size, not resolution.

Ok, let's assume you're right and osx upscale and then downscale...

If you render an "A" on 27" (3K) And sizes 30x30 pixels(900 pixels total) , to scale it to 5K the gpu will need to upscale and write total 3600 pixels (plus the 900 pixels from first rendering) , writing natively to 4K resolution only requires to write 1600 pixels total (only one time) , an big difference.

----------

I would love an iMac with a 5K screen, but it would have to be able to handle my 5K RED footage as well, at least in playback.
Doubt that will happen though, I could live with half res playback, and still see the full res image when paused

You need an Mac Pro late 2014 and the new 5K Dell monitor.

 

[Lava Lamp Freak]

No, this is for legacy apps, from lyon apps can be resolution independent (just as new iOS apps) so an guí element at same scree size will have the same relative real stare or foot print, despite if 1K,2K,4,8K of course as higher the resolution smoothest the lines.

No, displaying the same GUI element on 5K will require to render double the pixels, no scaling is done since everything is directly rendered on target resolution. This happened to legacy non retina optimized apps, also for pseudo optimized apps, native resolution independent apps show guí elements the same size independent the actual resolution or screen size, am good example it's Safari, compare it against ms word (non 360), also Web pages are natively rendered on target screen size, not resolution.

I call it scaling when I choose to use a resolution of 1920x1200 on a rMBP and it renders a 3840x2400 desktop and scales it down to 2880x1800. How can you say no scaling is done when that is exactly what is being done? Either you don't understand what is happening or you are using the wrong words to explain it.

Ok, let's assume you're right and osx upscale and then downscale...

If you render an "A" on 27" (3K) And sizes 30x30 pixels(900 pixels total) , to scale it to 5K the gpu will need to upscale and write total 3600 pixels (plus the 900 pixels from first rendering) , writing natively to 4K resolution only requires to write 1600 pixels total (only one time) , an big difference.

I understand that. That would be true if the 4k iMac was going to have tiny interface elements and wasn't released as a Retina iMac. What I'm saying is that for interface elements on a 4k 27-inch iMac to appear the same size as they do the current 27-inch iMac, it would have to render a 5k desktop and then downscale it to 3840x2160. An actual 5k iMac would render a 5k screen and display it at 5k. Either way a 5k desktop is being rendered, just on the 4k iMac there is an additional step to downscale it, resulting in a slightly fuzzy interface. The work for the GPU is the same, or slightly more on the 4k iMac since downscaling is required. I'm not aware of how much of a demand downscaling is.

My point is that your reasoning for there not being a 5k Retina iMac this year is not a valid reason because whether 4k or 5k it is the same amount of work for the GPU.

 

[Mago]

I call it scaling when I choose to use a resolution of 1920x1200 on a rMBP and it renders a 3840x2400 desktop and scales it down to 2880x1800. How can you say no scaling is done when that is exactly what is being done? Either you don't understand what is happening or you are using the wrong words to explain it.



I understand that. That would be true if the 4k iMac was going to have tiny interface elements and not a released as a Retina iMac. What I'm saying is that for interface elements on a 4k 27-inch iMac to appear the same size as they do the current 27-inch iMac, it would have to render a 5k desktop and then downscale it to 3840x2160. An actual 5k iMac would render a 5k screen and display it at 5k. Either way a 5k desktop is being rendered, just on the 4k iMac there is an additional step to downscale it, resulting in a slightly fuzzy interface. The work for the GPU is the same, or slightly more on the 4k iMac since downscaling is required. I'm not aware of how much of a demand downscaling is.

My point is that your reasoning for there not being a 5k Retina iMac this year is not a valid reason because whether 4k or 5k it is the same amount of work for the GPU.

You don't understand, having an native retina display doesn't means upscaled or downscaled, but having the same visual sized elements drawn on more dpi, not just an scaled image of an legacy GUI element, an new one with the same visual size of the non retina element.

No scaling it's required, and only one draw operation is done when guí elements are rendered (or drawn), for example, an font, you have 2 kind of font raster and vector, if your system uses raster based fonts you need an font image optimized for each dpi available on your system, if you don't have this image you need to upscale, downscale etc (as used to happen on legacy non retina optimized apps), but instead if you have vector fonts you don't it's directly drawn on the scree don't require to be scared since as a vector graphics the lines, arc etc are relative to the natural screen measures not the screen resolution, thus case you only need an single rendering operation, no multiple size images, no upscale, and you'll always get a optimal display, despite if retina, 2k, guí elements are drawn the same relative size. The same it's true for other guí elements as boxes, buttons, except raster images (which are upscaled or downscaled only once.

Whatever I bet you 2cts the next iMac is 4K and guí I keeps elements on the same size, no performance (if any) tax.

 

[Lava Lamp Freak]

You don't understand, having an native retina display doesn't means upscaled or downscaled, but having the same visual sized elements drawn on more dpi, not just an scaled image of an legacy GUI element, an new one with the same visual size of the non retina element.

No scaling it's required, and only one draw operation is done when guí elements are rendered (or drawn), for example, an font, you have 2 kind of font raster and vector, if your system uses raster based fonts you need an font image optimized for each dpi available on your system, if you don't have this image you need to upscale, downscale etc (as used to happen on legacy non retina optimized apps), but instead if you have vector fonts you don't it's directly drawn on the scree don't require to be scared since as a vector graphics the lines, arc etc are relative to the natural screen measures not the screen resolution, thus case you only need an single rendering operation, no multiple size images, no upscale, and you'll always get a optimal display, despite if retina, 2k, guí elements are drawn the same relative size. The same it's true for other guí elements as boxes, buttons, except raster images (which are upscaled or downscaled only once.

Whatever I bet you 2cts the next iMac is 4K and guí I keeps elements on the same size, no performance (if any) tax.

Yes, I do understand. You're describing functionality that doesn't currently happen in OS X. Currently when a 4k display is connected to a Mac, it renders a UI that is the same relative size as a display of the same size with a resolution of 1920x1080. (You know this is true since your signature shows that you own a 4k display.) What you seem to be claiming is that a 4k 27-inch iMac would render a UI that keeps the elements the same relative size as the current 27-inch iMac without doing any scaling. It would just natively render an interface with elements the exact same relative size as a 2560x1440 display instead of the way it currently does.

That would be great if Apple would release such an iMac. I'm in favor if it. I just don't see any evidence of such a thing being possible considering it would be completely different than how Macs currently handle a 4k display when connected. I'm not saying Apple won't do it. I'm just staying there is nothing I've seen to indicate it will happen. Do you have documentation or evidence to show why you believe such a thing will happen? The only evidence I've seen indicates the Retina iMac will be 5k.

 

[Mago]

Yes, I do understand. You're describing functionality that doesn't currently happen in OS X.......

I'm just staying there is nothing I've seen to indicate it will happen. Do you have documentation or evidence to show why you believe such a thing will happen? The only evidence I've seen indicates the Retina iMac will be 5k.

As you like SIR, i'm a C.S. Engineer I was programmer on Windows, Solaris and OSX, I cannot help you to understand what took years on a university classroom.

Evidence?

Simple: unless Apple invented am new std TB2 (dp1.2) can't drive a 5K resolution, so this hypothetic 5K iMac will be te first iMac w/o 2nd External monitor capability, same about GPU, actually there is no single GPU capable to drive 2 5K Monitors, as top the best dual monitor setup possible today on an single GPU (including the monstrous nVidia Titan) it's dual 4K.

 

[Lava Lamp Freak]

As you like SIR, i'm a C.S. Engineer I was programmer on Windows, Solaris and OSX, I cannot help you to understand what took years on a university classroom.

Evidence?

Simple: unless Apple invented am new std TB2 (dp1.2) can't drive a 5K resolution, so this hypothetic 5K iMac will be te first iMac w/o 2nd External monitor capability, same about GPU, actually there is no single GPU capable to drive 2 5K Monitors, as top the best dual monitor setup possible today on an single GPU (including the monstrous nVidia Titan) it's dual 4K.

DisplayPort 1.3 was recently released. Considering the timing, it is reasonable to expect the new iMac to support DP 1.3. I highly doubt Apple will release a 4k 27-inch iMac, but we'll know soon.

https://www.macrumors.com/2014/09/15/retina-imacs-displays-displayport-1-3/

 

[Mago]

DisplayPort 1.3 was recently released. Considering the timing, it is reasonable to expect the new iMac to support DP 1.3. I highly doubt Apple will release a 4k 27-inch iMac, but we'll know soon.

https://www.macrumors.com/2014/09/15/retina-imacs-displays-displayport-1-3/

Released not, defined it's another question and meaning, this means just two weeks ago manufacturers know how to implement dp1.3, the first product with dp1.3 it's month away from being announced.

I keep my bets high on this retina iMac to be 4K, the same for the Thunderbolt Display 2 or retina cinema display whatever it's named Apple successor of the Thunderbolt Display.

 

[Mago]

Yes, I do understand. You're describing functionality that doesn't currently happen in OS X.

Worth you read this https://developer.apple.com/library.../CocoaDrawingGuide/Transforms/Transforms.html

Specially the apart *resolution independent user interface*.

Also here you may understand it an bit better

https://developer.apple.com/library...d.html#//apple_ref/doc/uid/TP40012302-CH4-SW3
Enjoy your 5K iMac...

 

[Nutter]

Worth you read this https://developer.apple.com/library.../CocoaDrawingGuide/Transforms/Transforms.html
Specially the apart *resolution independent user interface*.

Lava Lamp Freak is correct.

While resolution independence was originally designed to work with any scale factor, integer or non-integer, Apple have only released products that use integer scale factors: ie. 2 pixels per point in each dimension, or in the case of the iPhone 6+, 3 pixels per point.

A hypothetical 4K 27" iMac would require a scale factor of 1.5 if UI elements were to stay the same size as they are right now. This wouldn't work so well because only every other point would be aligned to a pixel boundary. Besides, apps currently ship with bitmaps at 1x and 2x; the 2x versions would have to be downscaled to 1.5x, and that wouldn't look so good. As you say, Mago, fonts would be rendered well, but that's about all you can say in its favour. It's just not going to happen.

As LLF explained, the only other way to work with a 4k screen without changing the size of UI elements would be to render 2x at 5k and downsize the whole thing on the fly to 4k. This is basically what the iPhone 6+ is doing, but it's a trick that wouldn't work so seamlessly at the relatively lower PPIs we're talking about here. And as mentioned, in comparison to rendering to a native 5k display this would be harder, not easier, on the GPU.

 

[Mago]

Lava Lamp Freak is correct.

While resolution independence was originally designed to work with any scale factor, integer or non-integer, Apple have only released products that use integer scale factors: ie. 2 pixels per point in each dimension, or in the case of the iPhone 6+, 3 pixels per point.

A hypothetical 4K 27" iMac would require a scale factor of 1.5 if UI elements were to stay the same size as they are right now. This wouldn't work so well because only every other point would be aligned to a pixel boundary. Besides, apps currently ship with bitmaps at 1x and 2x; the 2x versions would have to be downscaled to 1.5x, and that wouldn't look so good. As you say, Mago, fonts would be rendered well, but that's about all you can say in its favour. It's just not going to happen.

As LLF explained, the only other way to work with a 4k screen without changing the size of UI elements would be to render 2x at 5k and downsize the whole thing on the fly to 4k. This is basically what the iPhone 6+ is doing, but it's a trick that wouldn't work so seamlessly at the relatively lower PPIs we're talking about here. And as mentioned, in comparison to rendering to a native 5k display this would be harder, not easier, on the GPU.

Still wrong.

IPhone 6 4.7 it's 1.5 x iPhone5 (or 3x iPhone 1).

I'll don't spend more time explain that (if you read yourself you'll find I'm right).

Also there are other reasons than such *integer* scaling:

Thermal: 5k requires to move 2x pixels, than 4k, requiring 2 gpu to get an user experience equivalent to the current iMac.

2nd external monitor: display port 1.3 has only 2 weeks since was defined, to drive an 5k monitor you need this or 2 dp1.2.

Finsl cost: while 4K panels now has the cost of last year QHD panels, there is only one 5K panel being produced now and cost 3x, add this the cost of dual GPU, and this 5k iMac will cost 3k or 4k $, while an 4k iMac would sell at same price with same design, the resolution *issue* it's an minor factor for Apple than the hardware challenge.

An 5K iMac is not practical (either useful) earlier than 2016.

 

[Serban]

an 5k iMac will be priced starting with $2499, and is not much for Apple standards...like macbook pro 15" started with high price but in 2 years the price gone down a few hundred bucks
so yes by the time we hit late 2016 the 5k imac will have a starting price $1999

 

[xgman]

I'm just thankful that you guys aren't designing this . . .

 

[jji7skyline]

But the GTX 970 only needs around 140 watts - see a comparison here.

That's still a huge amount of power to be cramming in such a small space.

In fact, the Late 2013 2.7Ghz iMac uses less than that for the whole computer!

http://support.apple.com/kb/ht3559

 

[Serban]

and the space in the imac is not for a high end desktop gpu

 

[johnnyturbouk]

I think Apple is actually making the right call here, as long as they pass the savings on to us.

<spits coffee out in astonishment> You are joking right?
Please tell me you can't be this naive?

 

[Spanky Deluxe]

That's still a huge amount of power to be cramming in such a small space.

In fact, the Late 2013 2.7Ghz iMac uses less than that for the whole computer!

http://support.apple.com/kb/ht3559

145 watts is for the desktop 970. The 970M looks to use about 95 watts and the 980M about 125 watts. Also, the power consumption listings from Apple only mention "CPU Max" and don't mention whether the graphics chips are being maxed out. I suspect it's not maxing out the graphics as the i5-4570R draws 65W at max and the 750M draws about 40W which together puts it over the 94W total system draw without factoring in the screen and everything else!

The performance of these chips is astounding and is a huge leap up over nVidia's previous generation and AMD's offerings. I know Apple still holds a grudge against nVidia due to all those failing GPUs a few years ago but it would be a real shame if the new retina iMacs were crippled with AMD graphics.

The 970M looks to offer about 40% more performance than AMD's best (and more expensive) mobile offering, the M290X all while drawing less power. The 980M offers about 30% more on top of that.

Still, at the end of the day, nothing will be able to push enough pixels to game at 5K on the 27" in modern games. At least a 980M should be able to play modern games smoothly at 1440p on the 27" though.

 

[LedCop]

DisplayPort 1.3 was recently released. Considering the timing, it is reasonable to expect the new iMac to support DP 1.3. I highly doubt Apple will release a 4k 27-inch iMac, but we'll know soon.

https://www.macrumors.com/2014/09/15/retina-imacs-displays-displayport-1-3/

Display Port 1.2 was released in December 2009 (late 2009).

Apple's first product to include it was the Retina MacBook Pro (late 2013).

That was a four year gap, I think due to Thunderbolt 2 only being released in mid-2013.

Display Port 1.3 might début in Apple products earlier than in four year's time, but I think that will depend on when Skylake is released as Skylake will bring Thunderbolt 3. Apple seems to implement Display Port versions only when corresponding Thunderbolt versions are available.

 

[Georgio]

I'm in the market for an iMac revamp as my current i7 27" is two years old and I always like to change every two years.

However if the new iMac changes to AMD mobile graphics I'll give it a miss and stick with my 680MX as that is better in every respect than AMD's offerings.

On the other hand if they announce a 970m/standard with a 980m as an upgrade I for one will be battering Apple's door down in order to be first in the queue with my money.

Their call.

 

[jji7skyline]

145 watts is for the desktop 970. The 970M looks to use about 95 watts and the 980M about 125 watts. Also, the power consumption listings from Apple only mention "CPU Max" and don't mention whether the graphics chips are being maxed out. I suspect it's not maxing out the graphics as the i5-4570R draws 65W at max and the 750M draws about 40W which together puts it over the 94W total system draw without factoring in the screen and everything else!

The performance of these chips is astounding and is a huge leap up over nVidia's previous generation and AMD's offerings. I know Apple still holds a grudge against nVidia due to all those failing GPUs a few years ago but it would be a real shame if the new retina iMacs were crippled with AMD graphics.

The 970M looks to offer about 40% more performance than AMD's best (and more expensive) mobile offering, the M290X all while drawing less power. The 980M offers about 30% more on top of that.

Still, at the end of the day, nothing will be able to push enough pixels to game at 5K on the 27" in modern games. At least a 980M should be able to play modern games smoothly at 1440p on the 27" though.

I wasn't talking about the 970M, because someone mentioned the GTX970 (Desktop Version) saying that it only uses 140W.

Of course Apple could use the mobile version.