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Intel's Haswell Moves Voltage Regulator On-Die

allanw Re:Heat (237 comments)

So what stops someone from taking the switching frequency really high, like into the hundreds of megahertz? In switching regulators, there is both conduction loss and switching loss. Conduction loss occurs from resistance in the power supply path, including switch resistance. It can be reduced by increasing the switching frequency. However, this increases the switching loss -- you have to switch the power FET gate capacitance more often. The most efficient system is achieved when conduction loss is balanced with switching loss. It is a complex engineering problem. By making a tiny package integrated solution, the inefficiencies of switching can be reduced so the frequency can go up. This cannot be easily done with a traditional discrete-based system like on current motherboards.

about a year ago
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Intel's Haswell Moves Voltage Regulator On-Die

allanw Re:Rotten idea for performance (237 comments)

If they can cut down platform costs by a few tens of dollars then it is a huge win. This solution removes a lot of discrete chips sourced from a lot of outside companies. Current voltage regulators for these 100W chips are multi-phase regulators, which means something like 4 - 12 parallel voltage regulators with their own inductors, etc. Also, the required area is 50x smaller according to their presentation, which directly affects form factor and cost of these systems.

about a year ago
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Intel's Haswell Moves Voltage Regulator On-Die

allanw Re:From a former power supply designer - Neat! (237 comments)

ARM chips are more like 10W, not 100W like high-performance CPU's. These power supplies are much more complicated to design. This is actually at the leading edge of R&D -- no other chip maker has made a commercial product with integrated voltage regulator in the 100W range. It's only been done in academia recently.

about a year ago
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Intel's Haswell Moves Voltage Regulator On-Die

allanw Re:Full presentation (237 comments)

The term "virus" in this context means a power virus -- which is an artificial workload designed to draw as much power as possible from the chip. For example, normal CPU burn stress tests might only activate 90% of the chip's power consumption, but a specially designed power virus would be able to activate all of it. In some cases designing the thermal and power integrity solution to support the chip's full power consumption under a power virus needlessly adds extra costs to a product, because it will never see that workload in real life. It's a virus because a malicious person might be able to activate this mode and melt down your CPU, so typically they _do_ have to design the system to support it.

about a year ago
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Intel's Haswell Moves Voltage Regulator On-Die

allanw Re:Full presentation (237 comments)

An Intel CPU has a TDP of 90W+ running under 1V. That's 100A+ from the switching power supply. With resistive loss, and inefficiencies from multi-phasing the regulators, efficiency are worse than you say. The cost is also high -- having all of this integrated into the package saves on the platform cost.

about a year ago
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Intel's Haswell Moves Voltage Regulator On-Die

allanw Re:Heat (237 comments)

As an EE, I like to think of Ohm's law as a definition for resistance. The resistance can be non-linear for active devices in which case using V = IR is quite useless.

about a year ago
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Raspberry Pi Hits 1GHz With Official 'Turbo Mode'

allanw Re:Ah, to be young again... (92 comments)

If you keep increasing the voltage then it's likely that you can hit higher frequencies, but the power scales with voltage squared and frequency linearly, so power will go up pretty quickly. However, nowadays in advanced processes the interconnect is becoming more of a factor in the limitation on frequency scaling instead of the transistors themselves, in which case increasing the voltage will only help up to a certain point.

The trade-off that the company selling the CPU's makes is between the cost of cooling, reliability and lifetime of the device (higher voltage will wear the transistors out quicker, and high temperatures accelerates this process), and yield.

about a year and a half ago
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Apple Seeks To Block 8 Samsung Products After Court Win

allanw Re:What's really funny... (396 comments)

Samsung is a huge conglomerate and the mobile division is certainly completely separated from their foundry and LCD businesses.

about a year and a half ago
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Victory For Apple In "Patent Trial of the Century," To the Tune of $1 Billion

allanw AAPL (1184 comments)

Well, I'm glad I have some AAPL stock.

about a year and a half ago
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Logitech Releases Washable Keyboard

allanw Re:Every keyboard is washable (205 comments)

Those ubiquitous black IC's are plastic packaging which is not moisture sealed. Not sure if it'd actually affect the silicon to soak it in water for a bit though and use normally. But if you ever order any parts, they come in moisture sealed bags with big warning labels saying that you must reflow solder the IC's within 24-72 hours of opening the package or else too much moisture from the air will seep into the packaging, causing them to act like popcorn when you bake them to 350C for soldering. So if you leave them out too long you're supposed to slowly bake them to get rid of all the moisture before reflow soldering.

about a year and a half ago
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Time Machines, Computer Memory, and Brute Force Attacks Against Smartcards

allanw Re:Neat trick... (49 comments)

Probably has some kind of exponential dependence on temperature as well, so I imagine there has to be a table storing the decay rate across temperature and voltage which also has to be specific for each manufactured chip.

about a year and a half ago
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Neal Stephenson Reinventing Computer Swordfighting, Via Kickstarter

allanw Gabe Newell HL3 cameo (151 comments)

If anyone didn't catch it, watch the video and there's a cameo of Gabe Newell forging a crowbar and saying "These things take time"

about 2 years ago
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Foxconn Invests $210 Million To Build New Production Line For Apple

allanw Re:Yes! (178 comments)

How is your usage of electronics products from company X any better?

about 2 years ago
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Diablo III Released

allanw Re:Hate to put a damper on the celebration (594 comments)

I don't really understand this argument. In Diablo 2, you could play single-player, but that character would never make it onto battle.net. Sure, you could just always play LAN games with your friends, but you'd never be able to take any of your progress online. Or if you go on open battle.net, anyone can just edit their save file and give themselves whatever items or levels they wanted. In Diablo 3, it's the same thing if you want to play your character on closed battle.net.

about 2 years ago
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Apple Quietly Updates iPad 2's Processor

allanw Re:Samsung processor (127 comments)

Same process, not same processor. And besides, Samsung's foundry is completely separate from their mobile business.

about 2 years ago
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Apple and Google Face Salary-Fixing Lawsuit

allanw Re:Any other such "secret" agreements out there? (402 comments)

Doubt it. The consumer electronics industry, including CPUs and GPUs, is keeping well in pace with the technology developed by semiconductor companies. Each new process node nowadays costs up to ten billion dollars to develop and put into production, and it's highly doubtful anyone is secretly hiding years of advancement over publically known technology. Now, if you want to talk about the companies keeping "hyperfast" architectures in wraps for slow release, then that is plausible, although still, highly doubtful.

about 2 years ago
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LightSquared Hires Lawyers To Prep For GPS Battle

allanw Re:not quite that simple (195 comments)

Is it worth paying twice as much for all of your GPS devices to be able to get Lightsquared?

more than 2 years ago

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