Testing the 27 "iMac" Thunderbolt - part V

Even in the video where the Mac Pro is traditionally at home, Westmere processors marking time: we find the fine balance between the raw frequency and the number of cores, which directly determines the performance for different applications. Handrake, for example, recognizes only core logic: this iMac is fighting against is with four cores to eight cores Westmere Mac Pro to € 3 400. But Handbrake does not take advantage of all the subtleties of Xeon processors, while the raw frequency is a key element of its operation: the iMac, with half of a good heart but more than the gigahertz Mac Pro, dominates with insolence. He can deal with anything against the twelve core Mac Pro to € 8 300: the frequency difference is less important than offset by the use of three times as many hearts.

The very marked differences in the Photoshop tests confirm the very different profiles of these machines. The DHT test uses a lot of old filters, so that the differences are erased in excess of five hearts (real and virtual) so the iMac is the hand with its higher frequency. The RAT test, it is much more realistic and simulates the touch of a photo with the latest filters: Although Photoshop performance peaked with massively multi-core configurations, the Mac Pro are Westmere at this time.

A beautiful iMac € 2 700 can be put in the closet of Mac Pro much more expensive? In most areas, yes, and widely: it shows, once again, the effectiveness of the Sandy Bridge Intel platform. The self in need of power will therefore turn to the iMac, which is not only the most powerful iMac ever made by Apple, but Mac is also one of the most powerful of the current range. The difference between these two lines is therefore not about raw power, but the concept: the iMac is an all-in-one, unlike the Mac Pro, which is still relevant for its scalability, ensuring a sustainability specific to dampen investment, therefore that represent the largest configurations. It also remains the machine of choice for certain niches, here for its computational capabilities, there to him the possibility of adding expansion cards. Still, the iMac is more than ever like the computer to do everything from Apple.

Testing the 27 "iMac" Thunderbolt - part IV

It is indeed one of the great surprises of this model: despite the powerful processor and the summer climate of the test period, the temperature of the iMac Sandy Bridge has remained surprisingly low levels. Most of the time, CPU temperature stays around 30 to 35 °: the ventilation system is effective and extraction points at the top of the screen and behind the foot, once hot, now warm. When exporting Aperture, the temperature rises to 48 °. A video encoding where the four cores are at 100% for 25 minutes? 55 °. The fans always keep the composure of the machine without a voice, a sharp contrast to the previous generation and some MacBook Pro Sandy Bridge.

This discretion only to mask the raw performance of the iMac Core i7: they reach or exceed those of most of the range Mac Pro. This is not the first time we see the top of the range iMac rival the Mac Pro or exceed, but it's the first time that the difference is so great and strong.

The distinction is clear: the common tasks, the iMac Core i7 overwrite the entire Mac Pro. It drives not only its direct rival, the Westmere Mac Pro 2.4 GHz or eight cores (€ 3,400), but offers the luxury of making lousy Westmere Mac Pro 2.93 GHz twelve hearts, a machine ... € 8 300! We cannot even say it's SSD benefit: the twelve core Mac Pro was tested with excellent Toshiba 512 GB SSD So Sandy Bridge architecture that works wonders on the cuts in the Finder or the export Garage Band or Aperture. Match almost zero on the export music with XLD.

A test like Cinebench shows that Westmere Mac Pro keeps the advantage in raw power; the iMac is above the Nehalem Mac Pro. The entire iMac line is better than the Mac Pro graphics side, a habit now.

(Cont.)

Testing the 27 "iMac" Thunderbolt - part III

Intel also provides the chipset of the iMac, a Z68 Series 6, replacing the P67 which had experienced numerous problems in the launch of the platform Sandy Bridge (SATA performance degradation). This chipset manages Smart Response, a new technology to use a SSD (up to 64 GB) as a cache for the hard drive, like the hybrid discs as the Seagate Momentus XT. Apple does not use this function: the SSD and hard drive of the iMac appear as two completely separate volumes. They are both connected to SATA III, allowing them to express themselves to their full potential.

The potential for the SSD is 240 Mb / s maximum throughput of 160 Mb / s of average flow. It's good but not dazzling, especially the hard drive of 1TB provided by Apple (a Western Digital Caviar Black 7200 RPM SATA III and 32 MB cache) is doing very well. The high density of its platters, SATA III interface and 32 MB cache allow it to reach speeds of around 120 Mb / s, with a fine linearity over large files.

Overall more efficient, the SSD, arranged in housing behind the SuperDrive, takes advantage of two areas: its access time and noise level. Fast, fast, fast, these are the three adjectives to describe what DSS quick fix on the MacBook Air and MacBook Pro, it is also on the iMac. While the scratch disk and is sometimes responsible for a certain delay, the SSD can boot the machine in a few seconds (12-14), forget the color wheel of death, and fluid in general operations, all in a royal silence accentuated by the presence of discrete fans.

(Cont.)

Testing the 27 "iMac" Thunderbolt - part II

The presence of two Thunderbolt ports used to connect the iMac 27 "to two external displays. You'll have no problem to connect two Apple Cinema Display 27": Use two mini-Display Port cable (same connector as the Thunderbolt), and any ... work of 81 inches diagonally. If you use a screen of another brand or a former Apple screen, you will need an adapter: your adapter VGA, DVI, HDMI to Mini Display Port working perfectly. The only problem will come from screens 30 "you should use a dual-link adapter, an active housing costing hundreds of Euros.

Otherwise, the ports are used to little Thunderbolt: devices using this new standard, although promising, will not arrive until mid-summer. Intended primarily for professionals, promises to be cost prohibitive and limited uses for the moment, the interest of this new connector is limited to the general public.

This is not the case for other race horses of the new iMac. The processor is an Intel Core i7-2600, the fastest second-generation Core i7. It has four physical cores, identified as eight logical cores (hyperthreading) clocked at 3.4 GHz. When an application does not use all cores but needs power, the processor can disable cores dynamically to increase the frequency of the remaining cores: it can go up to 3.8 GHz on a heart (Turbo Boost). With all reasonable thermal envelopes in this range, 95 W is worth mention (32 nm etching).

(Cont.)

Testing the 27 "iMac" Thunderbolt

Sandy Bridge processors, connectivity Thunderbolt, SSD are the elements that we begin to know well, together or separately, on many Mac. Put everything in a single iMac, and you get a real bomb.

The configuration we are testing today is the top of the line iMac: Screen 27 "of course, 4 GB of RAM DDR3 1333 MHz, an Intel Core i7 Quad 3.4 GHz, AMD Radeon graphics card HD 6970M with 1 GB of GDDR5 memory, hard drive 1 TB and 256 GB SSD could obviously put more RAM, disk drive 2 TB or the graphics card to 2GB, but as it stands, this configuration costs a whopping € 2699 - € 300 more than the Mac Pro "basic".

This iMac is first ... yes, an iMac. The problems therefore remain the same: a screen can be a bit too bright, an SD card reader a little too close to the SuperDrive ... This new generation, however, offers many small innovations: the webcam is now able to shoot HD 720p (even if the quality is more than average) while the USB 2.0 ports (4) FireWire 800 are joined by Thunderbolt ports. Also, the drives are now connected via SATA III (theoretical maximum of 6 Gb / s, the SuperDrive is in SATA II), and the WiFi card is connected to three antennas, which allows to use the iMac 2011 WiFi 802.11n three channels at 450 Mb / s.

(Cont.)