The 27-inch iMac (October 2015): the Flagship of the Heavenly lake

iMac with Retina 5K display was the first Mac om Intel Skylake inside, one of the first mass-market computers with a color palette of DCI-P3, and the world’s best in class “all-in-one” – judging by the publications of the time. In order to dive in the “heavenly lake”, the 27-inch iMac had to jump over a step (Broadwell). In the previous 27-inch processors 4th generation (Haswell) that, for the flagship line of desktop computers was totally unacceptable.

Heavenly lake, sorry for the explanation – it is the sixth generation of the Core architecture, Skylake. Which one of the main design goals was the economy – since the beginning of this great epic, the power consumption of processors has been reduced by 80 %, which is of course fine, but for everyone in the world has to pay. The performance of Intel compared to the third generation (Ivy Bridge) is almost not increased.

The era of laptops, almost Post-PC. This time, in processors for desktop systems, the performance note is in the list of priorities he was third after the economy and graphics. And it is with these processors history began Skylake.

Productivity growth was modest, but real – for the first time in several years.

This is a continuation of a series about the iMac on Intel, the previous parts are here:

The first part: the First Intel Mac – there are links to a series about the iMac G4 and iMac G5;
Second part: the Last “Behemoth” (eMac) and its Successor – there’s also links to a series about eMac;
Third part: Intel Core 2: and again the iMac to come…
The fourth part: Setbreak, or iMac Core 2 (IG)
Fifth part: iMac White, middle class.
Sixth part: 24-inch iMac, was it a special operation?
Seventh part: iMac aluminum not without extreme…;
Eighth part: the iMac becomes more powerful…;
Ninth part: iMac (Early 2009): the recession has affected Apple…;
Tenth: iMac (Mid 2009). the iMac is not for everyone…;
Eleventh part: Unibody iMac, remote control and mouse…;
The twelfth part: iMac (Late 2009) Core 2 processors, the younger model…;
Thirteenth part: iMac (Late 2009) Core i5/Core i7, overtaking Mac Pro;
The fourteenth part: More iMac’and for the same money. Apple 2010;
The fifteenth part: the Elite of the breed of iMac 2010;
The sixteenth part: the thunder and a home desktop computer…;
The seventeenth part: iMac (Mid 2011) – faster than a Mac Pro?;
Eighteenth part: the Last computer of the Steve jobs era;
The nineteenth part: iMac 21,5” (Late 2012): big iPad?;
Twentieth part: iMac 27” (Late 2012): now with Blu-ray;
Twenty-first part: iMac Core i3 March 2013;
Twenty-second part: iMac (21’5”, Late 2013) – speed bump, but not quite…;
Twenty-third part: the 27-inch iMac + Haswell + graphics for notebooks;
The twenty-fourth part: iMac (Mid 2014): it is not speed-bump;
Twenty-fifth part: iMac (Late 2014) with the screen 5K Retina;
Twenty sixth part: iMac (Mid 2015): adding to the family iMac Retina 5K;
Twenty-seventh part: iMac economy class (October 2015);
The twenty-eighth part: the 21.5-inch iMac with Retina 4K display.

That was evident

About what’s inside the 27-inch iMac the new generation of Intel processors with the poetic name Skylake, users might not know. Life is short and should not waste it on that are interested. Do what you love and know.

Nevertheless, the users of this “smart display” is delighted. From a variety of. Was it something rushing in my eyes. Screen. The year before, in October 2014, something similar has already happened. Retina 5K, an engineering masterpiece, with incredible clarity of text and all that. It would seem, what else can surprise the audience jammed?

It turned out – can. For most nonsense like “color palette” meant nothing. A quarter of a larger number of colors and shades – that sounds attractive, but what these marketers with advertisers do not make up the work they have such.

But the screen was better, color richer and richer, it was obvious even to the layman. Even eternally dissatisfied professionals, this time, estimated it positively. The ideal tool for a wide range of specialties. Unusual.

In the store, side by side, standing enabled iMac Retina 5K of 2014 and 2015, and the difference between them was evident. Despite the fact that both screens were the best in its kind, and the screen 2014 was also brighter.

And yet the eye is an incredible number of inaccuracies in the review, strange even for that time. Once (I caught this time) Mac was against the gray mass, seized almost the whole world, and defended them on his heart (don’t believe the skeptics, this fact is of fundamental importance). Now they wrote ordinary people they risked nothing, and that what you write was indifferent.

I do not argue – probably, so be it, but for some reason the days when it was not so and the “Apple world” was on the verge of death, are remembered as the most vivid in my life.

iMac “heavenly lake”, prose

In variants of the model with ID iMac17,1 was used in three versions, Intel Skylake-S and four versions of discrete graphics processors from AMD.

Technical features of the iMac Retina 5K 2015 determined by the capabilities of Skylake-S, although some of these opportunities were ignored.

Skylake Thunderbolt supported 3, but at 17.1 was used in Thunderbolt 2. Even such innovations are not ignored: they are carefully studied, experimented with them, and considered what it would cost for their application, and how it will improve the final product. And if the balance was not in favor of innovation, so much the worse for him.

All processors used in large iMac 2015 was integrated graphics 9th generation Intel HD Graphics 530, level GT2 – ignored her, turned off and not used. To work with 14 million pixels the GPU these obviously were not good.

Bluetooth 4.0, to work with the magic devices (Magic Keyboard and others like it) was enough. Bluetooth 4.2 would increase the cost – and in a world where almost every food processor it is supported by the effect of this would be negligible.

In the cheapest option was used in a hard disk of 1 TB (7 200 rpm), with a write speed of at amounted to 197.6 MB/s and reading in 201,1 MB/s, which for 2015 was not that unheard of, but very out of date. But even at a price of 1 799 dollars its margin (the difference between price and cost) has remained within the specified limits.

For the same reason, the basic configuration was completed with 8 Gigabytes of RAM. Type of RAM – PC3-14900 DDR3 (1 867 MHz) SDRAM SO-DIMM. If increasing (buying), the margin is strictly enforced. Therefore, the memory cost to buy on the side of the Apple it was more expensive.

Greed is the engine of progress (if not beyond), but the margin is one of the options which investors evaluate the company’s activities and products whose circulation significant reduction is highly undesirable.

Minimize costs, maximize improving all that made sense, the engineering masterpiece was turned into a commercial masterpiece. Happened.


In iMac17,1 processors Skylake-S in three versions (all – 4-nuclear):

— Intel Core i5 3.2 GHz (i5-6500), with 6 MB cache in the third level, the maximum frequency is 3.6 GHz , no Hyperthreading support, TDP 65 Watt;
— Intel Core i5 3.3 GHz (i5-6600), 6 MB cache third level, a maximum frequency of 3.9 GHz , no Hyperthreading support, TDP 65 Watt;
— Intel Core i7 4.0 GHz (i7-6700K) 8 MB cache third level, a maximum frequency of 4.2 GHz, supports Hyperthreading – 4 physical cores, 8 virtual, 91 Watt TDP.

For data exchange with peripherals processors Skylake used the third version of the Direct Media Interface with a transmission capacity of 8 Gigatransfer per second (instead of 5 GT/s DMI 2).

The processor installed in socket LGA 1151, and any of them is relatively easy to replace with another that is compatible with this socket with a TDP not exceeding 91 Watt.

Graphics processors used in iMac17,1 – four of them, they are designed for use in laptops middle and upper classes. Desktop luxury they fit. Technology 28 nm manufacturer – TSMC:

— AMD Radeon R9 M380 (Strato Pro), performance 1 152 GLOPS, 128-bit bus, GDDR5, TDP, presumably, 70-75 Watts;
— AMD Radeon R9 M390 (Pitcairn), performance 1 962 GLOPS, 256-bit bus, GDDR5, TDP of about 100 Watts;
— AMD Radeon R9 M395 (Amethyst Pro), performance 2 989 GLOPS, 256-bit bus, GDDR5, TDP 125 Watts;
— AMD Radeon R9 M395X (Amethyst Pro), performance 3 723 GLOPS, 256-bit bus, GDDR5, TDP 125 Watts.


In the online store (and in retail) had three options, 1 799, 1 999 and 2 $ 299. All of these options (they are the same – the initial configuration) was quite viable in the OS X “El Capitan” 10.11 and immediately ready to perform their duties after unpacking, but for serious work was needed more.

In configurations 1 1 799 and $ 999 used the same processor, Intel Core i5 3.2 GHz (i5-6500).

In option 1 799 dollars installed AMD Radeon R9 M380 with 2 GB GDDR5, 8 GB PC3-14900 DDR3 (1 867 MHz) SDRAM SO-DIMM and hard disk of 1 TB (7 200 rpm). The outlet for connection SSD (PCIe x4) were available even in this case, everything can be corrected after acquisition. And on the back side of the case, was a hatch for access to RAM.

In the Configurator’s RAM can be increased up to 32 GB (4 modules of 8 GB), outside of an Apple – to 64. Instead of the hard disk can be purchased Fusion (24 GB SSD + 1 TB, 128 GB SSD + 2 or 3 GB) or SSD in 256, 512 and 1024 GB. But the option of replacing the processor with a more powerful for this option in the Configurator was not, but the processor installed in socket LGA 1151.

In option 1 for $ 999 was AMD Radeon R9 M390 with 2GB of GDDR5, the same 8 Gigabytes of RAM and a Fusion Drive 24 GB SSD + 1 Terabyte. The Configurator offers all the above options except the hard drive.

And for $ 300 you can order Intel Core i7 4.0 GHz (i7-6700K).

Option 2 $ 299 (which was blamed for the high cost, but agreed that it is worth the money) used Intel Core i5 3.3 GHz (i5-6600), AMD Radeon R9 M395 with 2GB of GDDR5, in the configuration included Fusion c hard disk capacity of 2 Terabytes (128 Gigabytes of flash memory).

Among the options of the Configurator for this option was the Intel Core i7 4.0 GHz (i7-6700K), AMD Radeon R9 M395X with 4 Gigabytes of GDDR5.

To be continued

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0 Comments on “The 27-inch iMac (October 2015): the Flagship of the Heavenly lake”

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