Graphics: A substantial bump

There are three new GPUs in the new iMacs: the AMD Radeon 6750M, 6770M, and 6970M. Unlike their desktop counterparts, the 6750M and 6770M are true 6000-series GPUs, and not just rebadges of the 5750 and 5770 (though, as always, making direct comparisons between desktop and mobile parts remains difficult).

On the entry-level iMac, the 256MB Mobility Radeon HD 4670 has been replaced by a 512MB Radeon HD 6750M – you get double the graphics memory, a switch from GDDR3 to GDDR5, DirectX 11, OpenGL 4.1, and OpenCL 1.1, as well as Eyefinity+ and UVD3 and the other Radeon 6000-series niceties. For gamers, this should substantially improve performance, especially if you’re interested in trying to game at the 21.5” iMac’s native 1920x1080 resolution.

Moving up the chain to higher-end models, the 512MB 6770M isn’t as big a step up from the previous generation’s 512MB Mobility Radeon 5670 – like the desktop cards, the 6770M is essentially a higher-clocked and gently tweaked revision of its previous-generation counterpart, and higher clocks are likewise all that separate it from the 6750M. You pick up UVD3, but a lot of the on-paper specs are the same. It’s still an improvement over the previous generation, but compared to the low end and (as we’ll see) the high end, it’s not as substantial.

And, finally, we’ve arrived at the high end 27” iMac, which gets a 1GB 6970M to replace last year’s 1GB Mobility Radeon 5750. The 5750 is more or less a midrange graphics part – the mobility 5600 and 5700 series GPUs all share the same core, codenamed Madison – but the 6970M is a true high-end part, complete with a 256-bit memory bus (compared to a 128-bit bus for the 5750) and more than double the shaders (960 in the 6970 versus 400 in the 5750). This, again, will drastically improve the new iMac’s utility as a gaming machine – the 6970M is much more capable of driving the 27” iMac’s 2560x1440 pixel display. Update: Further research has revealed that the 5750 that shipped in last year's iMac was in fact a rebadged member of the mobility 5800 series using the "Broadway" core instead of the "Madison" core used in Mobility 5600 and 5700 parts. The 5800 series has 800 shaders and not 400, so while the bump in the new 2011 iMac is still a decent one, it's not as monumental as previously reported.

For the 27” models with two Thunderbolt ports, the 6000-series GPUs will also enable the use of three displays simultaneously, which will be handy for the Final Cut and Photoshop junkies who often invest in the higher-end iMacs.


The last thing I want to talk about is the subtle factor looming over these refreshed computers: Lion.

OS X 10.7 is supposed to bring a lot of iOS features “back to the Mac” when it releases this summer, and since these Sandy Bridge Macs are going to be the first computers the new OS ships on, we’re seeing some preparation for it on the hardware end.

To drive the iOS inspired touch enabled features, each new iMac can come bundled with either the touch-enabled Magic Mouse or the Magic Trackpad at no extra cost (it’s your choice – the Magic Mouse is the default option). The vanilla Apple Mouse is still a selectable option, but will save you no money compared to its touch-enabled counterparts, which are more expensive at retail.

Apple is also beginning to push SSDs in its laptops to replicate the quick boot and shutdown times of iOS, and we’re beginning to see that in the new iMacs – while none of the computers include an SSD by default, you can configure all but the entry level to include a 256GB SSD as either the primary hard drive or a secondary drive. Characteristically, Apple hasn’t posted anything about the manufacturer of this drive or its controller – Apple uses Toshiba SSDs in the Sandy Bridge MacBook Pros, and recently switched to Samsung SSDs for the MacBook Airs, but there’s really no telling exactly what these iMacs are packing until it’s in your hands.

To replace the mechanical hard drive with a 256GB SSD costs a whopping $500 ($600 to get the SSD and keep the mechanical hard drive as well), though that’s not too far above the market price for an SSD at this capacity. Also note that, at this point, TRIM only seems to be enabled in OS X for SSDs direct from Apple – even if you can put in an SSD as an aftermarket upgrade, you may not be as satisfied with its performance. This may change in Lion, but we have no solid evidence to that effect.


With this refresh, Apple has done what Apple typically does: offer faster hardware in a similar physical package while maintaining price points across the board. Quad core processors and beefier dedicated GPUs make these better buys, relatively speaking, than last year’s models, but the iMac is still the iMac: a midrange-to-high-performance all-in-one with a high-quality display. Today’s upgrades do nothing to change the iMac lineup on a fundamental level.

That is to say, if you were in the market for an iMac already, congratulations! Today’s iMac is faster and more capable than yesterday’s iMac on all fronts. If an iMac isn’t what would best suit your purposes, though, today’s update won’t do much to change your mind unless you were looking for better gaming performance on the low and high ends.

For more about the nitty-gritty on the new iMac's performance and internals, keep an eye out for our in-depth review in the coming weeks.

Specs and CPUs
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  • AddFunction - Tuesday, May 3, 2011 - link

    I agree w/ Spazweasel. I've used ms computers since the 80's & 3 years ago I got a MacBook. Not cheap, but not that expensive & a pleasure to use. No virus issues, security updates, constant housekeeping & maintenance. I still have 2 Win 7 computers but I think I'll stay w/ Macs from now on. Windows is just too much bother & I just don't enjoy that anymore.
  • seapeople - Tuesday, May 3, 2011 - link

    What exactly do you do to your computers that you need "constant housekeeping & maintenance" on Windows 7? Do you live on a porn site and frequent password cracking sites with admin access for fun?

    Oh I get it, I bet you're one of those XP freaks who insisted on disabling UAC and tweaking your registry so clicking on "My Documents" opens up a customized user interface where one click opens the file you select and two clicks opens the file below it.

    Really, if your Windows 7 needs constant user intervention to provide housekeeping and maintenance then you're using it wrong, and the only reason you think Macs are better is because you listen to Steve Jobs when he tells you that you're using those wrong.
  • psychobriggsy - Wednesday, May 4, 2011 - link

    Or maybe he ran out of patience with Windows and PCs three years ago (maybe Vista was the last straw), and Windows 7 is just too late to matter any longer to him.

    He is right - using a Mac is no headache compared with Windows, and once you're past a certain age you realise that you've better things to be doing as you race towards old age than fiddlearsing around with a computer.
  • chillmelt - Wednesday, May 4, 2011 - link

    That applies to me. But I still choose Windows over a Mac. I found that overclocking and strenuous amount of gaming is one of top causes of software/hardware malfunction on computers, PC or otherwise. I hardly play games now, and I've yet to experience any crashes since I stopped gaming.

    Now excuse me while I enjoy VMWare running Mac 10.6.2 on my Windows PC without the Mac "tax" or performance plummet.
  • seapeople - Wednesday, May 4, 2011 - link

    Ok, now I get you. Even though he likes Windows 7 like most everyone on the planet, he has been burned by Windows too much in the past to care. I'm in the same boat. I bought a Lisa, so in my mind every Apple computer made today is complete junk and I will thus freely make outdated claims against Apple.
  • ananduser - Wednesday, May 4, 2011 - link

    Spazweasel, how can you post such idiocies ? No seriously. How do you know how PC users are or how mac users are ? It sounds more like you are a mac user because you perceive macs as suggested to you via marketing. You bought a mac wanting to be what you portray the typical mac user to be, and you strongly believe that you are a "superior" user. This is AT, a tech enthusiast's site. What are you doing here acting like a douche stereotyping everyone who uses a PC? So what if PC users do not agree and do not credit Apple's macs, marketing and doctrine; doest it affect you esteem or what ?

    Man, it is unbelievable how identical hardcore mac fans are. In my country they hold annual mac themed meetings and praise the enlightened despot that is SJ( actual words used ). They spew the same idiocies like you with the platform superiority and the ULTRA synergetic,ergonomic,unisex,revolutionary and whatnot. They even wish well for MS(their perceived enemy) so as the unwashed masses keep to the inferior platform. Well if such is the case in an eastern European country, where Apple is extremely low profile, I can only imagine how the mac "clubs" in USA are. After all Apple is the only tech company that has an ultra loyal following, a fan base instead of an user base.
  • akm3 - Tuesday, May 3, 2011 - link

    I *personally* don't care about BluRay but your point stands. The 4GB RAM is certainly pretty lame too (as well as the overpriced hard drive and difficulty to upgrade).

    However, no eSATA and no USB 3.0 is kind of a false argument with Thunderbolt and Firewire 800 (and USB 2)

    Thunderbolt > eSATA and USB 3.0....if you're willing to invest in (mostly non-existent today) peripherally to attach to it.
  • Targon - Wednesday, May 4, 2011 - link

    And there are dozens of Thunderbolt devices ready to go? New technologies always take some time from release to when devices become available. The only reason for the lack of USB 3.0 is because Intel can't get it out at this point.

    If AMDs Bulldozer really does provide the improvements that have been mentioned in terms of CPU performance, that really will do some very interesting things for the industry, since AMD already has USB 3.0 ready to go.
  • Wizzdo - Tuesday, May 3, 2011 - link

    Yawn. Always the same old boring "It's too expensive...blah blah blah" half-baked comments.

    You make your money back on resale alone with a Mac.

    We all have the same organs but that does not mean we all use them the same. Macs are designed to run amazingly well with OSX. They are like a well-designed, finely-tuned automobile that provides users with YEARS of satisfaction.

    I just installed the latest OSX Snow-Leopard on a 6 year old Macbook Pro and it makes that machine feel and run as if it was brand new. Another happy customer.

    Windows machines look like crap, run like a hodge-podge, and make you feel like upgrading to a mac within a couple of years. And you can barely give away that OLD hunk of junk you thought you saved money on 2 years ago.

    You get what you pay for. If you want cheap plastic crap with no support that is obsolete within a few months and will require half-a-day to upgrade to the next Windows super-overpriced non-professional-version Vista-fix (that you would probably have been better off installing from scratch), then you have no right posting your nonsense here or anywhere else for that matter.

    Best of luck with your soon-to-be landfill donation.
  • Tamz_msc - Wednesday, May 4, 2011 - link

    Typical comment (as expected) from iSheeple.

    If you have some basic knowledge, Windows based PCs run amazingly well too.
    Windows is well designed, and it has given me YEARS of satisfaction, and I'm sure that is also the case with countless other Windows users.

    I installed Windows 7 last year on my old PC(1.86 GHz Core 2 Duo, 1GB RAM, 8600GT, 250 GB HDD) and it runs great.

    ITS WE WHO DECIDE HOW OUR PC WILL LOOK LIKE, not Jobs. It all depends on how much you spend, what parts you buy etc.A Windows machine like this:
    looks a thousand times better than a boring white iMac, and performs better than any of you iSheeple could ever imagine.I guess you're too happy with some shiny white case and Steve Jobs' propaganda to be bothered about the cheap parts inside your Macs like motherboards which come from companies like FOXCONN, where workers are worked to their DEATH.

    You also get what you pay for- shine white poop which gets updates once in six months, gets new hardware only after mainstream Windows PCs,who get them much earlier, some OS that you feel is the best but has been proven to be vulnerable time and again.

    Continue dreaming about the superiority of your beloved Mac..............

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