6Gbps SATA

Twenty eight days after Intel launched its Sandy Bridge microprocessors, it announced the stop-shipment of all 6-series Sandy Bridge chipsets. The first shipping version of these chipsets (B2 stepping) was affected by an unfortunate "oversight" that could cause failure in the four 3Gbps SATA ports that branch off the chipset. The remaining two 6Gbps SATA ports were unaffected by the bug.

Most notebooks only use two of the six SATA ports supported by most members of Intel's 6-series chipset family. If a notebook design used the 6Gbps ports exclusively, the notebook would be fine to ship using the flawed B2 stepping parts. With the 3Gbps ports not in use the bug would never show up. Notebooks that used more than just two ports or used at least one of the 3Gbps ports would be affected and would have to be remanufactured with a fixed version of the 6-series chipset. Intel promised to begin shipping fixed (B3 stepping) 6-series chipsets by the end of February.

Apple announced and started selling the 2011 MacBook Pro lineup on February 24, four days before the end of the month. Surely that would be too soon for Apple's manufacturing partners to have received B3 stepping chipsets, built boards around them, integrated them into MacBook Pro designs and shipped them half way across the world to Apple stores all around the US.

Naturally Apple wouldn't comment on what chipset revision was in the 2011 MacBook Pro, so the first thing we did was check to see what SATA ports were in use on our systems.

Here we have the high end 15-inch MacBook Pro. I installed an Intel SSD 510 in the lone 2.5" drive bay and it is connected via a 6Gbps port internally:

So far, so good. The only other bay in the new MacBook Pro is used for the optical drive. And it's connected to a:

...3Gbps SATA port. Uh-oh.

Apple doesn't directly report chipset IDs under OS X. I installed Windows 7 via Boot Camp and headed over to device manager to pull the device ID of the SATA controller: 1C01.

Cross referencing with Intel's datasheets I found that there are two revisions of the SATA controller: 04 and 05. The latter is used in the "fixed" B3 stepping chipsets. And what do we have here at the end of the hardware ID string for the SATA controller?

REV_05.

This is a B3 stepping chipset. In fact, Apple's manufacturing partners seem to have received B3 chipsets before anyone else given that boards were produced, tested and shipped in time for a February 24th launch. It would appear that Apple was among the first if not the first company to receive B3 stepping 6-series chipsets. Although I had concern for the health of the Apple/Intel relationship over the past couple of years, it looks like the two are back to being bedfellows.

Internally there are no visible changes to the MacBook Pro's primary SATA cable. It's still a flex cable but apparently capable of delivering twice the bandwidth of last year's model. Apple doesn't ship the new MacBook Pros with any 6Gbps drives and I would be surprised if it selected anything other than Samsung or Toshiba for SSDs, which means even the SSD options are 3Gbps. Luckily I happen to have a small cache of SSDs, including a bunch of new 6Gbps offerings.

Mostly No QuickSync Apple's SSD Strategy
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  • IntelUser2000 - Friday, March 11, 2011 - link

    You don't know that, testing multiple systems over the years should have shown performance differences between manufacturers with identical hardware is minimal(<5%). Meaning its not Apple's fault. GPU bound doesn't mean rest of the systems woud have zero effect.

    It's not like the 2820QM is 50% faster, its 20-30% faster. The total of which could have been derived from:

    1. Quad core vs. Dual core
    2. HD3000 in the 2820QM has max clock of 1.3GHz, vs. 1.2GHz in the 2410M
    3. Clock speed of the 2820QM is quite higher in gaming scenarios
    4. LLC is shared between CPU and Graphics. 2410M has less than half the LLC of 2820QM
    5. Even at 20 fps, CPU has some impact, we're not talking 3-5 fps here

    It's quite reasonable to assume, in 3DMark03 and 05, which are explicitely single threaded, benefits from everything except #1, and frames should be high enough for CPU to affect it. Games with bigger gaps, quad core would explain to the difference, even as little as 5%.
    Reply
  • JarredWalton - Friday, March 11, 2011 - link

    I should have another dual-core SNB setup shortly, with HD 3000, so we'll be able to see how that does.

    Anyway, we're not really focusing on 3DMarks, because they're not games. Looking just at the games, there's a larger than expected gap in the performance. Remember: we've been largely GPU limited with something like the GeForce G 310M using Core i3-330UM ULV vs. Core i3-370. That's a doubling of clock speed on the CPU, and the result was: http://www.anandtech.com/bench/Product/236?vs=244 That's a 2 to 14% difference, with the exception of the heavily CPU dependent StarCraft II (which is 155% faster with the U35Jc).

    Or if you want a significantly faster GPU comparison (i.e. so the onus is on the CPU), look at the Alienware M11x R2 vs. the ASUS N82JV: http://www.anandtech.com/bench/Product/246?vs=257 Again, much faster GPU than the HD 3000 and we're only seeing 10 to 25% difference in performance for low detail gaming. At medium detail, the difference between the two platforms drops to just 0 to 15% (but it grows to 28% in BFBC2 for some reason).

    Compare that spread to the 15 to 33% difference between the i5-2415M and the i7-2820QM at low detail, and perhaps even more telling is the difference remains large at medium settings (16.7 to 44% for the i7-2820QM, except SC2 turns the tables and leads by 37%). The theoretical clock speed difference on the IGP is only 8.3%, and we're seeing two to four times that much -- the average is around 22% faster, give or take. StarCraft II is a prime example of the funkiness we're talking about: the 2820QM is 31% faster at low, but the 2415M is 37% faster at medium? That's not right....

    Whatever is going on, I can say this much: it's not just about the CPU performance potential. I'll wager than when I test the dual-core SNB Windows notebook (an ASUS model) that scores in gaming will be a lot closer than what the MBP13 managed. We'll see....
    Reply
  • IntelUser2000 - Saturday, March 19, 2011 - link

    I forgot one more thing. The quad core Sandy Bridge mobile chips support DDR3-1600 and dual core ones only up to DDR3-1333. Reply
  • mczak - Thursday, March 10, 2011 - link

    memory bus width of HD6490M and H6750M is listed as 128bit/256bit. That's quite wrong, should be 64bit/128bit.

    btw I'm wondering what's the impact on battery life for the HD6490M? It isn't THAT much faster than the HD3000, so I'm wondering if at least the power consumption isn't that much higher neither...
    Reply
  • Anand Lal Shimpi - Thursday, March 10, 2011 - link

    Thanks for the correction :)

    Take care,
    Anand
    Reply
  • gstrickler - Thursday, March 10, 2011 - link

    Anand, I would like to see heat and maximum power consumption of the 15" with the dGPU disabled using gfxCardStatus. For those of us who aren't gamers and don't need OpenCL, the dGPU is basically just a waste of power (and therefore, battery life) and a waste of money. Those should be fairly quick tests. Reply
  • Nickel020 - Thursday, March 10, 2011 - link

    The 2010 Macbooks with the Nvidia GPUs and Optimus switch to the iGPU again even if you don't close the application, right? Is this a general ATI issue that's also like this on Windows notebooks or is it only like this on OS X? This seems like quite an unnecessary hassle, actually having to manage it yourself. Not as bad as having to log off like on my late 2008 Macbook Pro, but still inconvenient. Reply
  • tipoo - Thursday, March 10, 2011 - link

    Huh? You don't have to manage it yourself. Reply
  • Nickel020 - Friday, March 11, 2011 - link

    Well if you don't want to use the dGPU when it's not necessary you kind of have to manage it yourself. If I don't want to have the dGPU power up while web browsing and make the Macbook hotter I have to manually switch to the iGPU with gfxCardStatus. I mean I can leave it set to iGPU, but then I will still manually have to switch to the dGPU when I need the dGPU. So I will have to manage it manually.

    I would really have liked to see more of a comparison with how the GPU switching works in the 2010 Macbook Pros. I mean I can look it up, but I can find most of the info in the review somewhere else too; the point of the review is kind of to have it all the info in one place, and not having to look stuff up.
    Reply
  • tajmahal42 - Friday, March 11, 2011 - link

    I think switching behaviour should be exactly the same for the 2010 and 2011 MacBook Pros, as the switching is done by the Mac OS, not by the Hardware.

    Apparently, Chrome doesn't properly close done Flash when it doesn't need it anymore or something, so the OS thinks it should still be using the dGPU.
    Reply

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