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Intel Claims Haswell Architecture Offers 50% Longer Battery Life vs. Ivy Bridge
MojoKid writes "As with any major CPU microarchitecture launch, one can expect the usual 10~15% performance gains, but Intel apparently has put its efficiency focus into overdrive. Haswell should provide 2x the graphics performance, and it's designed to be as power efficient as possible. In addition, the company has further gone on to state that Haswell should enable a 50% battery-life increase over last year's Ivy Bridge. There are a couple of reasons why Haswell is so energy-efficient versus the previous generation, but the major reason is moving the CPU voltage regulator off of the motherboard and into the CPU package, creating a Fully Integrated Voltage Regulator, or FIVR. This is a far more efficient design and with the use of 'enhanced' tri-gate transistors, current leakage has been reduced by about 2x — 3x versus Ivy Bridge."
Math tip: A 50% increase in battery life (what they actually claimed) isn't the same as doubling it.
Also, since a big selling point for Haswell (aside from power efficiencies) is the claimed greatly improved (~2x for laptop-oriented models, ~3x for desktop-oriented models) improvement in graphics performance, I'd be very surprised if their claims for about battery life were focussed on systems using discrete GPUs rather than relying on the integrated graphics on Haswell.
Well, except that they explicitly claimed that was overall battery life, and it was a 50% increase not 2x, and they actually cited numbers for improvement in idle life and it was much higher than the +50% claimed overall (or even the 2x you pulled out of who-knows-where), since their claimed idle-mode improvement was twenty times (TFA is less clear on this, but Computerworld covers the same event with more specificity: "And in idle or standby mode the chips will do even better, extending battery life by up to 20 times, [Rani Borkar, Intel's Architecture Group VP] said." [emphasis added])
This means you are going to have to 1) have redundant regulation on the mo-bo for other components,
Nope. Motherboards already had dedicated regulators just for the CPU.
High-speed CPU core logic needs very low supply voltages, around 1.0V these days. Lower speed parts built in older processes need higher voltages -- 1.2V, 1.5V, 1.8V, or more. There's not much on the motherboard which even can share supplies with the CPU. Also, CPUs now dynamically vary their own core voltage (by sending commands to the regulator) in order to save power. That wouldn't work so well with other chips sharing the same regulator.
It's been a very long time since the regulators which powered the CPU core also powered any other chips on the motherboard.
and 2) subject your CPU to much higher (and unregulated) voltages. You've added another heat generation source right there on the CPU, and power excursions are likely to take out your processor.
Who said the input to a regulator must be unregulated? Current x86 systems already convert one regulated voltage to others. The ATX power supply outputs regulated 12V DC to the motherboard, which is then converted to several low voltages to supply the CPU and other devices. Haswell's integrated voltage regulators accept 1.8V input, so in practice they're going to be fed by a 1.8V regulator on the motherboard.
Heat doesn't appear to be that big a deal. The top desktop TDP bin is going from 77W (Ivy Bridge) to 84W (Haswell). The total system power is going down, not up -- despite the extra conversion step, the integrated voltage regulators offer efficiency gains.
(One is that it's now practical to have a lot of independent power domains. Haswell apparently has no less than five independent power planes. This makes it possible to dynamically adjust the voltage of different portions of the chip independently, giving a better match between activity level and power use. Another gain is that it's difficult and inefficient to supply a very low voltage at very high current over long distances. This is why nobody was ever even slightly interested in extending the ATX spec to supply ~1.0V directly to the CPU. Haswell puts the high current / low voltage supply as close to the load as it possibly can go.)