Nanotech - The Circuits Blog

If the speculation about a new MacBook Pro is on the money, the step up to Intel's quad-core mobile technology would have a profound impact on this vaunted line of Apple laptops.

Is a Core i series Apple laptop on the way?

(Credit: Apple)

So, why would Apple adopt a Core i processor in a laptop? The short answer is OS X Snow Leopard. The new operating system is designed to be better at wringing more performance out of multicore processors--and the Core i chips pack four cores.

The long answer is the Core "i" chips themselves. The Core i, a.k.a. "Nehalem," is a brand new Intel microarchitecture brimming with performance improvements over the current Core 2 design.

For starters, the recently announced mobile i7-820QM processor integrates a hefty 8MB of cache memory--compared with the 6MB in the fastest Core 2 Duo that Apple currently offers on the MacBook Pro. Generally, the larger the cache memory, the better the performance.

But Intel has done a lot more than just up the transistor count via a larger cache. While the quad-core i7-820QM is rated at 1.73GHz, a single core can be "overclocked" to 3.06 GHz. Intel does this with a technology dubbed Turbo Boost, which speeds up and slows down individual cores to meet processing and power-efficiency needs, respectively.

Need more convincing? The Core i7 also comes with Hyper-Threading, which can double the number of tasks--or threads--a processor can execute. You won't find that in the Core 2 chips.

Digital media creation also gets a boost. Intel claims up to 81 percent faster video encoding.

And the mobile Core i7 is not a power hog--relatively speaking. The i7-820QM is rated at 45 watts, less than a third of the power envelope of the desktop Core i7. With such a powerful processor, heat would be an issue of course but the 45-watt power envelope is manageable.

That said, there are reports that Apple is not bringing out any more products this year. So, along these lines, alternatively, Apple could opt initially for the upcoming "Arrandale" Core i chips--due by the beginning of next year--that are based on a more advanced 32-nanometer manufacturing process. (Current Core i processors use a 45-nanometer process.)

Arrandale integrates graphics silicon into the same chip package as the main processor--a first for Intel. Because of this high level of integration, Arrandale, however, is a dual-core chip.

But probably the closest thing to a rumored MacBook Pro refresh is the iMac, which has the same space-constrained characteristics of a laptop. The quad-core Core i7 in the new iMac "boosts application performance up to 2x over the previous-generation iMac," according to Apple--and that's what consumers can expect with a Core i series laptop.

A report claiming that Nvidia has been ousted from Apple laptop designs has gained prominence quickly because the graphics chip supplier is still dogged by past problems.

"The word is that Nvidia is out of Apple designs," according to a June 26 report from technology Web site SemiAccurate. The report has been cited widely with varying degrees of credence given to it.

"When I say out, I mean on the Nehalem-based Macs," Charlie Demerjian, the author of the report, said in a phone interview Monday, referring to future laptops from Apple that will be based on Intel's new Nehalem Core i series of chips.

Nvidia, not surprisingly, doesn't see it that way. "These rumors are baseless," an Nvidia spokesman said Monday. Apple had no comment.

Nvidia graphics processors are currently used widely in Apple MacBooks. And Apple has been touting a new technology in its upcoming Mac OS X Snow Leopard operating system called OpenCL, which takes "the power of graphics processors" and makes it available to Snow Leopard for everyday computing tasks.

However, lurking below this push to tap into the compute power of the graphics processor lie past issues with Nvidia chips. A May 29 Apple knowledge-base article (Article: TS2377) couches frustration with Nvidia in diplomatic language, according to Demerjian. The article updates a similar notice Apple published in October of last year.

"Nvidia assured Apple that Mac computers with these graphics processors were not affected," according to the Apple May 29 statement. "However, after an Apple-led investigation, Apple has determined that some MacBook Pro computers with the Nvidia GeForce 8600M GT graphics processor may be affected."

"The 8600M referred to in the Apple support page...had a particular material set," Nvidia said Monday, repeating a statement it has made several times in the past. "That particular combination of material set is no longer being used by Nvidia."

In a May 20 disclosure as part of a Form 10-Q filing with the Securities and Exchange Commission, Nvidia said that some notebooks still have problems associated with its graphics chips.

And past statements from not only Apple but the world's largest PC makers lend weight to the tenor of SemiAccurate's assertions about Nvidia's chip problems, if not necessarily to the accuracy of the report's claims about Nvidia's future at Apple. Hewlett-Packard said last year that it had been grappling with Nvidia chip issues since November 2007. And Dell made a similar statement last year.

Writing about the SemiAccurate report, Broadpoint AmTech analyst Doug Freedman said Monday: "If the reports are indeed true...Although negative at the margins, this shortfall could be offset by new product ramps." Freedman cited upcoming products--that will offset any negative impact--such as Nvidia's Tegra chip for smartphones and its Ion chipsets for laptops and Netbooks.

Nvidia was hit by a Standard & Poor's ratings downgrade Wednesday, according to a Dow Jones report, adding to the graphics chipmaker's woes.

Standard & Poor's ratings services ratcheted down its outlook on Nvidia from positive to stable, according to Dow Jones. S&P cited concerns about the graphics chipmaker's sinking revenue and profitability.

The ratings agency maintains a junk-level BB- grade on the company, and S&P noted that revenues from Nvidia's recent efforts to expand into cell phones, handheld devices, and supercomputer applications is small, according to Dow Jones. Nvidia also faces new competition from Intel's upcoming Larrabee graphics chip, S&P said.

In addition, Nvidia has been grappling with graphics chip issues on laptops. Apple issued a fix Wednesday for the graphics problems suffered by some owners of the new 17-inch MacBook Pro.

Not everything was bad news for Nvidia Wednesday, however. Ironically, on the same day, Broadpoint AmTech analyst Doug Freedman upgraded Nvidia to "buy" from "neutral" saying that "our checks indicate an improving top-line allowing the company to grow from a larger revenue base...as the trough appears less deep than originally thought," he wrote in a research note.

"Although we remain cautious on gross margin mix we do believe that (operating expenditures) are ahead of expectations, potentially adding leverage to our estimates," Freedman said.

Advanced Micro Devices worries that lingering issues--both real and speculative--with Apple MacBooks are giving laptop graphics a black eye.

In a phone interview Tuesday, Stan Ossias, director of marketing, mobile graphics, at AMD, began by asserting that my March 11 post "overstated" the case about heat and the instability of graphics processors in laptops and that some readers may interpret heat issues too broadly.

"In the case of Apple's product, I don't know what happened with Nvidia's GPU but we'd like to avoid having the negative aspects taint the entire industry," he said. (GPU stands for graphics processing unit.)

Most recently, there have been reports of performance issues with Apple's new 17-inch MacBook Pro, which has the Nvidia GeForce 9600M chip. But it's unclear whether Nvidia's chips are really the problem and it's not known how widespread the issues are.

Ossias started off the discussion by spelling out how AMD mobile graphics processors can adjust performance and power consumption to different conditions. (The technology, it should be noted, is applied in various ways by many graphics chips.)

"When the system is calling upon the GPU to do more work, we either increase the voltage or increase the clock speed or increase the operating attributes of the system in order to maximize the performance, and when those things are not in demand we can scale them back so they're not constantly being run at their maximum. This is the way we go about trying to avoid overheating," he said. Strict implementation of these design parameters is particularly critical in systems where there is the greatest potential for overheating: thin notebooks and high-end gaming notebooks, according to Ossias.

AMD provides tools to PC makers, he said, who make the final design decisions on how the GPU will perform in different power-usage scenarios. But sometimes the laptop maker won't make the best choice.

"Somebody may choose a GPU that doesn't necessarily have the best operating characteristics or doesn't deliver the optimal power consumption in all operating ranges. That's a constant development challenge" for laptop makers, he said, then added: "A very, very large proportion of our customers do a very good job of this."

"I don't think Apple does a bad job of this in general. They are extremely meticulous generally," he said. However, in some cases "a product decision is made (where) maybe there is more emphasis put on performance characteristics than on another characteristic. Again, that's another choice that can be made," Ossias said.

Ossias gave an example of the type of graphics chip that would not go into the new MacBook Pro, which is about an inch thick. At the high end of its mobile graphics chip lineup, the ATI Mobility Radeon 4870 can draw as much as 45 watts--a big power draw for a mobile chip. Due to these power characteristics, this would not go into a thin form-factor notebook like the new MacBook Pro, he said.

AMD announced new mobile GPUs last week based on a cutting-edge 40-nanometer process

(Credit: AMD-ATI)

Last week, AMD announced groundbreaking mobile GPUs, the ATI Mobility Radeon HD 4830 and 4860, based on a cutting-edge 40-nanometer process. Both chips compete in the same general performance category as the 4870 but start at a much lower power-consumption level (the low 20-watt range) and "therefore you can actually get the 4830 into a thin and elegant notebook design," according to Ossias. AMD's current 4650 and 4670 can fit into thin form factors also, he said. These latter two chips would be in the same class as the Apple MacBook Pro's Nvidia GeForce 9600M, he claimed. The 9600M is the chip alleged to have heat and performance issues.

"I know that when Nvidia announced (in October of last year) publicly that it was recalling or having to rework some of its products and they took a big write-down, we had to address concerns from our customers that we were not also experiencing packaging failures because of the overheating and design flaws that they were experiencing in their product line," he said. "So, we basically had to go and calm down a lot of our customers and say, look, this is not something that's inherent to our technology, it's not something that you have to expect from any GPU."

Nvidia is again at the center of a graphics tempest in the media, this time surrounding performance issues of Apple's new 17-inch MacBook Pro. Two little pesky questions haven't been answered yet, however. Are Nvidia graphics chips really the problem? And are the issues really that widespread?

Postings in an Apple discussion forum cite a smorgasbord of problems: Some cite the Nvidia GeForce 9600M, while others point to issues with fan speed. Another post points to faulty wiring and another to the main processor (i.e., Intel). But this is just one forum. Does this really indicate widespread problems?

Does the Apple MacBook Pro 17-inch unibody have chip issues?

(Credit: Apple)

I haven't heard back from Apple. Nvidia had no comment Monday.

So, I spoke with a few people who have informed insights into potential problems. Not all would speak on the record, however. Jon Peddie of Tiburon, Calif.-based Jon Peddie Research, which tracks the graphics chip market and does testing on graphics chips, said he hasn't tested the new MacBook Pro yet. Generally speaking, however, a GPU problem of this sort would dictate a BIOS change to adjust the fan speed (one of the possible solutions proposed already). Or, if it's more serious, the graphics board would need to be replaced. (BIOS stands for basic input-output system; GPU stands for graphics processing unit; CPU stands for central processing unit.)

"If either of those conditions were true, Apple would be issuing an alert," he said. The alternative is for Apple to deal with the alleged problem on a piecemeal basis, one customer at a time, Peddie said.

The latter scenario--the status now--of course leads to a lot of speculation and attempted diagnoses among users.

I also contacted another analyst, Linley Gwennap, principal analyst at the The Linley Group. He made some obvious points but important in the context that it's not necessarily the GPU. Basically he said that if any chip exceeds the "thermal design budget," the system becomes unstable.

Other people I contacted (who wished to remain anonymous) said the issue appears to be more of a fan issue than a GPU issue. But the jury is still out. And, let's be clear, Nvidia has been faulted for past MacBook glitches. The most recent being in October. Will Nvidia be perpetually plagued by fallout from past problems? The 1994 Pentium FDIV bug was an Intel albatross for years.

I see another ancillary issue--not necessarily directly related to the MacBook Pro issue discussed above--that needs to be addressed. Here's the proposition: you want better graphics but you also want a sleek laptop like the Apple MacBook Pro. Well, if you're pushing the outside of the graphics-performance envelope, something's got to give. It's like saying: I want a car that goes from zero to 60 in under four seconds but with low emissions.

The truth is high-performance discrete GPUs and Intel CPUs--even the ones with the "m" (for "mobile") suffix--will sometimes wreak havoc when they're stressed inside enclosures only 1-inch high (i.e., many laptops). But I'm stating the obvious (I think). Anyone who has maxed out a relatively high-performance GPU or CPU in a laptop knows the real meaning of the euphemism "uncomfortably hot"--a phrase often used in discussion forums.

Overheating results in a lot of unpleasant (and sometimes seemingly unrelated) surprises, including BSOD (Blue Screen Of Death), automatic (arbitrary) shutdown, and, as in the case of the MacBook Pro, graphics artifacts.

Some people will always point their finger at Nvidia (or ATI) but I submit that some of those people experiencing problems would be the first to raise a stink if Nvidia didn't offer a high-performance laptop graphics chip to run Crysis at the frame rates and resolutions they demand. Yes, a product should work as advertised but there are limits to what a GPU (or CPU) can do inside the thermally challenged, cramped quarters of a laptop.

Not that Nvidia is absolved of any and all crimes. Far from it. As I stated above, Nvidia has had its share of problems that were its own fault. But even Intel's integrated graphics (theoretically the most power efficient) has heat gotchas of its own. Heat has been an issue in the first version of the Intel-graphics-based MacBook Air (when playing video)--which I can vouch for since I own a first-generation MBA. And I have another laptop (from a top-five PC maker) with integrated graphics that immediately heats up (and sometimes overheats) when running video.

But back to discrete GPUs. If you want desktop-level graphics in your sleek laptop, then you're going to have to take the heat and, consequently, in some cases--if you push the graphics card--instability and graphics anomalies. That doesn't make it right. It's just a fact of life.

Bad bumps? A U.K. tech site is alleging that the latest Apple MacBook Pros contain Nvidia graphics chips with the same "bad bumps" problem that Nvidia addressed this summer and said was rectified.

Nvidia said in a phone interview on Tuesday that this is dead wrong.

First a little background. Nvidia issued a statement July 2 saying it would take a charge of up to $200 million to cover repairs due to a "weak die/packaging material set in certain versions of its previous generation GPU and MCP products used in notebook systems."

Both Hewlett-Packard and Dell have come out with statements addressing the issue in laptops. And both companies have programs that try to fix the issue.

U.K. tech site The Inquirer is saying that bad bumps--"tiny balls of solder that hold a chip to the green printed circuit board"--are still present in the GeForce 9600 graphics chips that ship in the newest MacBook Pros. An issue that The Inquirer claims is the root of the problem.

The Web site said it took a MacBook Pro off a store shelf, disassembled it, desoldered the chips, sawed them in half, encased them in Lucite, and ran them through a scanning electron microscope equipped with an X-ray microanalysis.

As a result, The Inquirer alleges that the MacBook Pros with the GeForce 9600 chips have the older, defective high-lead bumps, while the MacBook Air and MacBook have the newer eutectic solder (newer, low-lead bumps).

So, in essence, the MacBook and MacBook Air are fine, while the MacBook Pro is problematic.

Nvidia vehemently disagreed with the allegations, calling them completely untrue. The Inquirer's "initial analysis of problems with some of the older chips was already flawed," said Michael Hara, vice president, investor relations and communications at Nvidia.

The Inquirer reporter "believes high-lead bumps are bad. That's his underlying theory. It's not true," Hara said.

He continued: "When you build a device, it's the material properties and everything in combination that leads to the robustness of the design. What we call the 'material set.' It's a combination of the underfill (a kind of a glue that helps hold the chip down) and the bump together that creates that stability in that connection," he said.

Hara talked about how the original problem announced by Nvidia on July 2 was rectified. "A more robust underfill would have taken the stress off the bumps and kept that (original problem) from happening. What we did was, we just simply went to a more robust underfill. Stopped using that (previous) underfill, kept using high-lead bumps, but we changed the underfill. And now we don't see the problem."

"Intel has shipped hundreds of millions of chipsets that use the same material-set combo. We're using virtually the same materials that Intel uses in its chipsets," Hara said.

Hara also said Taiwan Semiconductor Manufacturing Company (TSMC) ships a "staggering" number of chips to many companies worldwide with high-lead bumps. TSMC is the world's largest contract chip manufacturer and makes chips for Nvidia, Advanced Micro Devices, and many other companies.

Nvidia also issued this written statement: "The GeForce 9600 GPU in the MacBook Pro does not have bad bumps. The material set (combination of underfill and bump) that is being used is similar to the material set that has been shipped in 100's of millions of chipsets by the world's largest semiconductor company (Intel)."