Slashdot Mirror
AMD Launches Low-Voltage Processors
mgoulding writes "CoolTechZone reports that AMD has released its low-power Athlon processors, which are designed to target the ultra-lightweight notebook market. The low-voltage chips will use smaller batteries and produce less heat. Acer plans to ship systems using the processors by the end of May." Acer plans to use them in their Ferrari line of thin laptops.
here is some tech info in case it gets /.ed
The other models - 2800+, 3000+, and 3200+ are rated to operate at 65W while the 2700+ is rated to operate at 35W. The Pentium M processor models - 1.5Ghz, 1.6Ghz, and 1.7Ghz are set to operate at 24.5W. The AMD 2700+ budget Mobile processor still consumes more power than the Centrino platform, which uses Intel's Pentium M chips. Another big difference between the rest of Athlon64 Mobile processors from AMD and the 2700+ budget level Mobile processor is the amount of L2 cache. The 2700+ processor has 512KB cache while the rest of the models house 1MB cache. The 2700+ is clocked at 1.6Ghz; the same clock speed as the 2800+, which has 1MB L2 cache.
Marge, get me your address book, 4 beers, and my conversation hat.
Voltage is a squared term in the general power function for a CPU. Lowering the voltage will have a significant effect on power consumption. As you might imagine, the chip's operating frequency is another term in the function.
~Someday, I hope to be an aspiring author.
Actually, because of the way CPUs are binned to meet market demand, overclocking a CPU isn't necessarily doing anything to it that's bad. All CPUs are tested after fabrication and sold according to their capabilities. In the event that demand for a lower end processor is high, a processor that tests well can be marked as and sold as a lower-end model. It's still the same processor it was when it was tested, though. In this case, you might drop a CPU into your computer and experience exceptional overclocking potential. I have an XP1600+ that overclocks to 2200+ at default voltage and works ideally under a torturous FAH load. In fact, you could view the chip as being underclocked at the factory instead of overclocked by the user! :)
Cooling is an important factor, but its nowhere near as important as good luck (or picking a good stepping).
~Someday, I hope to be an aspiring author.
The announcement is of the mobile, low-voltage Athlon 64, not just the mobile, low-voltage Athlon -- which has been in the very machine I'm typing on for nearly a year. This is referenced in one place in the article, but the chips are misleadingly referred to simply as "Athlon" in the title, and several more times.
Share and Enjoy: 09 F9 11 02 9D 74 E3 5B D8 41 56 C5 63 56 88 C0
No. Ohm's law is in play. Charging a capacitor takes in energy, yes, but that energy is stored as charge, not radiated as heat. The heat comes from I^2*R loss. The I part comes when the capacitor must be charged.
So, it's really pretty simple. Lower voltages mean that the capacitors don't take in as much charge, and therefore don't require as much current to charge up. Less current == less I^2*R loss == less power consumed.
You can get similar improvements by reducing the size of the capacitances, which can be done by reducing the size of the FET gates... which means a smaller feature size.
You are correct that the transistors look mostly like capacitors, but you are incorrect in stating that power is stored in the junction and that creates heat. Power is dissipated in the interconnects, sources and drains, and in the vias between layers. This is also one big reason why we went to copper - lower resistance interconnects == less power lost to resistance.
Ce n'est pas un vrai mouvement de robot!
Or do the next best thing:
1) Buy an Athlon 64 PC
2) Enable PowerNow! power management
3) Buy a power supply with a variable-speed fan (I recommend this one) and enable CPU fan speed control on the motherboard (Q-Fan in ASUS's BIOS, IIRC).
When you're just reading Slashdot, the CPU runs at 800MHz and power consumption drops waaay down. When you're playing UT2004, the CPU runs flat out and the fans speed up. It works extremely well.