Apple introduced two new all-in-one iMacs May 3, and repair site iFixit quickly picked up a 21.5-inch model for a teardown that perhaps only a true tech geek could love. Rendering the aluminum-and-glass head-turner into a pile of shiny bits, they found an Intel Thunderbolt port not quite identical to the model in the new MacBook Pros, the same LG Electronics display Apple used on the not-yet-a-year-old previous iMac line, and a big win for Atheros as well as Intel.
Apple outfits the smaller iMac with a 21.5-inch LED-backlit glossy widescreen TFT display with support for millions of colors and a resolution of 1920 by 1080 pixels-perfect for affixing two heavy-duty orange suction cups to, to get things underway."Our suction cup gamble paid off," Miroslav Djuric, iFixit's director of technical communication, wrote in a May 4 statement. "We found very soon that this iMac model opens in the same way as previous generations. All you have to do is pull off the magnetically held display glass with two medium-size suction cups, and then remove the screws holding the LCD in place."An early find was the Mac Book's Thunderbolt I/O port. Developed with Intel, the port is designed to offer two bi-directional channels with transfer speeds up to 10G bps each-making it speedy enough to transfer an HD movie in less than 30 seconds, by Intel's count. That the PCI Express and DisplayPort each get their own speedy data channels, iFixit noted in a blog post, is nice, "as you don't want your display competing with your external hard drive for bandwidth."From there the teardown team disconnected three antennas, removed a few screws and popped the AirPort card out of its socket."The big winner in the wireless communication area this time around is Atheros," said Djuric. "At the heart of the WiFi card is an Atheros AR9388-AL1A 802.11n wireless LAN chip."From there, things looked not so different from the previous 21.5-inch iMac. The team removed a hard drive, the SATA data/power connectors and the LED driver board. Next out was a Sony Optiarc optical drive, which revealed a bare spot where they guessed the SSD-an optional feature on the 2.7GHz model-would go. From there it was out with the audio line-in and line-out ports and the IR board-another leftover from the previous model that Apple made use of, which could "simply be lifted straight up and removed from the iMac's front bezel," Djuric said.A lot more jiggling was required to get out the logic board."In usual Apple fashion, one heat sink is reserved for the CPU, while the other oversees the GPU," iFixit reported. "And, in usual Apple fashion, you have to void the warranty in order to get a peep at the processing power underneath."One imagines, however, that anyone who has made such a mess of such a formerly sleek, lovely object has probably already committed to this idea.Apple is happy to share that the graphics on its is 21.5-inch model are either an AMD Radeon HD 6750M processor with 512MB of GDDR5 memory or a 6770M processor with 512MB of GDDR5 memory. The model iFixit picked up sports the former, which it found shares space on the GPU with four Hynix 1Gb GDDR (graphics double data rate) SDRAM chips, for a total of 512MB. Peeling back a final sticker warning-"Warranty void if removed"-the team took a look at the iMac's Intel Core i5 CPU with 6MB of Intel Smart Cache."Thankfully," they reported, "the CPU and GPU on this machine have proper amounts of thermal paste applied, a happy departure from the gobs applied to the MacBook Pro we recently took apart."In other good news, the GPU heat sink detaches from the logic board, exposing the AMD GPU board. "You heard that right, folks," wrote Djuric. "You don't have to replace the entire logic board if your GPU explodes from too much l33t gaming."Neighbors on the logic board are iMac's Intel Core i5-2800S CPU, an Intel platform controller hug, a Broadcom integrated gigabit Ethernet and memory card reader controller, a Cirrus audio controller, a controller for the USB ports, an Intersil voltage regulator for the GPU core power applications, and the Thunderbolt port IC.All told, the team found that the RAM, hard drive and optical drive can be replaced with relative ease, the LCD isn't terrible to remove, the limited use of adhesives make disassembly pretty straightforward, and replacing the CPU and GPU are possible but not ideal. However, removing the logic board is "a pain," and good luck reassembling the LCD and glass without getting dust stuck between them.Beating the MacBook Air by a mile, in terms of teardown friendliness, the new iMac scored a "very respectable" 7 out of 10 on the iFixit's repairability scale.Available now, the new iMacs start at $1,199.