The notebook industry promises increased battery run times, but the advances are in fact small, and run times still mainly depend on the power provided by the notebook battery. More efficient processors and platforms, drives and LED-backlit displays certainly help a lot. Real leaps, however—say to 10+ hours of battery life—just aren’t within reach.
The electrical draw of the system isn’t constant; it varies depending on the state of the each component. Displays are the largest power-eaters, as they have to operate transistors and their backlight—larger and higher resolution displays typically require more power than smaller ones. But there is also quite a power requirement range among notebook system components.
Modern notebook processors may require little power when there is nothing to do, but they can go up to 35 watts of power consumption at full load, depending on the processor model and power classification. Notebook platforms using graphics units built into the chipset are the most efficient, while notebooks utilizing a discrete mobile GeForce or Mobility Radeon always consume at least a bit more power than integrated solutions. In terms of storage, flash SSD drives have the potential to deliver impressive throughput and quick access times with very little power consumption. Most devices require considerably less power when they are idle, so it makes sense to operate your notebook as close to idle as possible, to maximize battery run time.
While there are alternative energy sources on the horizon, such as silver-zinc batteries (see ZPower), none of them are ready to be deployed into the mainstream right now, where huge quantities of batteries are required. Notebooks typically utilize lithium-ion or lithium-polymer batteries, which are organized into so-called “cells” (typical capacities are three, six, or sometimes nine cells). While the power level of a battery depends on the specific model, a 6-cell battery will generally give you twice the battery run time of a 3-cell model. Battery capacities are rated in Watt-hours (Wh).
The 9-cell batteries obviously provide the most juice, but they are often too large to be accommodated within the standard rectangular notebook footprint, and hence stick out a bit from the back. To expand capacity without this physical size expansion, some notebook vendors offer additional modular batteries that can be inserted instead of a machine’s optical drive; these are especially common on portable business notebooks (13-15”).
Source tomshardware.com
Thursday, April 2, 2009
Wednesday, April 1, 2009
AMD’s Low Power Advantage
AMD, dominated the processor market with its Athlon 64 and Athlon 64 X2 just a few years ago, was able to make a return with the recent Phenom II processors. While these new 45 nm CPUs cannot trump Intel's Core i7, they offer performance that can match a Core 2 Quad here and there. Unfortunately, there is no low-power version available yet, so we decided to look at AMD’s remaining low-power option.
The latest Athlon X2 dual-core CPUs are very affordable, and supposedly efficient. Our shootout includes an Athlon X2 5050e (45 W TDP) and a 5600+ (65 W TDP) as well as several Intel processors.
Low Power
Power users will certainly focus on performance first, while all other users want to have the best of both worlds: a fast processor that does not consume more power than necessary.
Performance is easy enough to define. It is the time required for a workload to complete, or workload execution within a given time. However, efficiency is still sometimes misunderstood, because efficiency does not equal low power. A low-power device such as Intel’s Atom processor has low power consumption, but it is far from being efficient.
We define efficiency as the power that is required to complete a specific workload. In this case, power is measured in Watt-hours (this isn’t watts per hour, but watts times hours). Some readers had noted that work energy should be stated in joules. One joule equals one watt-second, so a watt-hour equals 1 x 60 x 60 = 3,600 joules. We decided to stay with Watt-hours (Wh), as this is the way we are charged for electricity.
CPU Power
On the CPU side, AMD has traditionally had two advantages over Intel. First there is the SOI manufacturing process (at 90, 65, and 45 nm), which ensures low power requirements in idle mode thanks to low leakage power. This makes it very much competitive with Intel’s manufacturing, which has typically been 12-18 months ahead of AMD with regards to transistor size (note that AMD processor manufacturing is being outsourced). Second, AMD processors have come with integrated memory controllers since the introduction of the Athlon 64 in late 2003, which typically provides a power consumption advantage over logic that is part of the Intel chipset. Core i7 has started to introduce a paradigm change in this direction with Intel, but that doesn’t apply to Core 2.
So there is the platform, which contributes to power consumption. Especially if you look at all-in-one integrated chipsets such as the AMD 780G, AMD has offered much better 3D performance and power efficiency than Intel chipsets. We used an integrated AMD 780G motherboard as well as an Intel board based on the latest G45 chipset for this article, as well as two representative AMD processors, two Intel dual-cores chips, and two Intel low-power quad core CPUs.
Source from tomshardware.com
The latest Athlon X2 dual-core CPUs are very affordable, and supposedly efficient. Our shootout includes an Athlon X2 5050e (45 W TDP) and a 5600+ (65 W TDP) as well as several Intel processors.
Low Power
Power users will certainly focus on performance first, while all other users want to have the best of both worlds: a fast processor that does not consume more power than necessary.
Performance is easy enough to define. It is the time required for a workload to complete, or workload execution within a given time. However, efficiency is still sometimes misunderstood, because efficiency does not equal low power. A low-power device such as Intel’s Atom processor has low power consumption, but it is far from being efficient.
We define efficiency as the power that is required to complete a specific workload. In this case, power is measured in Watt-hours (this isn’t watts per hour, but watts times hours). Some readers had noted that work energy should be stated in joules. One joule equals one watt-second, so a watt-hour equals 1 x 60 x 60 = 3,600 joules. We decided to stay with Watt-hours (Wh), as this is the way we are charged for electricity.
CPU Power
On the CPU side, AMD has traditionally had two advantages over Intel. First there is the SOI manufacturing process (at 90, 65, and 45 nm), which ensures low power requirements in idle mode thanks to low leakage power. This makes it very much competitive with Intel’s manufacturing, which has typically been 12-18 months ahead of AMD with regards to transistor size (note that AMD processor manufacturing is being outsourced). Second, AMD processors have come with integrated memory controllers since the introduction of the Athlon 64 in late 2003, which typically provides a power consumption advantage over logic that is part of the Intel chipset. Core i7 has started to introduce a paradigm change in this direction with Intel, but that doesn’t apply to Core 2.
So there is the platform, which contributes to power consumption. Especially if you look at all-in-one integrated chipsets such as the AMD 780G, AMD has offered much better 3D performance and power efficiency than Intel chipsets. We used an integrated AMD 780G motherboard as well as an Intel board based on the latest G45 chipset for this article, as well as two representative AMD processors, two Intel dual-cores chips, and two Intel low-power quad core CPUs.
Source from tomshardware.com
GeForce GTX 285 On Water Cooling
Zotac's Infinity Edition : Why Water?
Liquid cooling takes advantage of the key features that a larger radiator offers compared to local sinks, with the added benefit that the radiator can often be mounted in a cooler air stream.
That explains why a large radiator sits at the front of most automobiles, but in the case of overclocking, complexity and inconvenience have limited the number of liquid-cooling applications in PCs. Most liquid cooling systems focus on the CPU, since adding other components to the loop makes servicing a nightmare. In particular, removing a liquid cooling system from graphics cards requires extreme caution and plenty of extra time to drain the system, which must then be refilled and re-purged (to remove air from the water lines) before it can be used again. This could easily turn five minutes of diagnostic work into a one-hour ordeal--and that's if you know what you're doing.
But liquid cooling’s inconveniences can be more easily justified in situations where air cooling simply isn’t adequate. We’ve run into this exact problem when overclocking multi-card graphics configurations, and our December $2,500 3-Way SLI PC was the most noteworthy example. Packing three double-slot cards together limited airflow to the intake fans of the top two cards, so that cooling was barely adequate to keep up with the configuration’s stock speed.
For overclockers, the opportunity to seek significant performance gains makes liquid cooling’s troubles worthwhile, and several companies are ready to fulfill those needs. Options include buying an air-cooled card and adding an expensive liquid-cooling “water block” or purchasing a card with the water block pre-attached, such as the GeForce GTX 285 Infinity Edition from Zotac.
Liquid-cooled graphics cards typically cost around $50 less than the sum of their parts (high-end water block plus a high-spec card), so the smart money for anyone looking to water cool is to buy these parts pre-assembled. Zotac adds one more reason to purchase its product by pre-overclocking its GPU and RAM to extra-high speeds, selling the card with a warranty that home overclockers typically must sacrifice. That also means that each GTX 285 Infinity Edition is hand-selected for its ability to support the rated speeds, while the purchaser of a reference-clocked card must rely on the luck of the draw to reach similar or greater speeds.
Overclockers aren’t the only market for liquid-cooled electronics, as similar methods have been used to address airflow constraints in densely packed servers. And let’s not forget home-theater and audio-studio applications where liquid cooling allows enormous passive radiators to suffice in situations that would have otherwise called for noisy high-speed fans. All of these markets share a common goal of increased cooling capacity at reduced use of local space and these are things that even non-overclocking performance enthusiasts can appreciate.
Source from www.tomshardware.com
Liquid cooling takes advantage of the key features that a larger radiator offers compared to local sinks, with the added benefit that the radiator can often be mounted in a cooler air stream.
That explains why a large radiator sits at the front of most automobiles, but in the case of overclocking, complexity and inconvenience have limited the number of liquid-cooling applications in PCs. Most liquid cooling systems focus on the CPU, since adding other components to the loop makes servicing a nightmare. In particular, removing a liquid cooling system from graphics cards requires extreme caution and plenty of extra time to drain the system, which must then be refilled and re-purged (to remove air from the water lines) before it can be used again. This could easily turn five minutes of diagnostic work into a one-hour ordeal--and that's if you know what you're doing.But liquid cooling’s inconveniences can be more easily justified in situations where air cooling simply isn’t adequate. We’ve run into this exact problem when overclocking multi-card graphics configurations, and our December $2,500 3-Way SLI PC was the most noteworthy example. Packing three double-slot cards together limited airflow to the intake fans of the top two cards, so that cooling was barely adequate to keep up with the configuration’s stock speed.
For overclockers, the opportunity to seek significant performance gains makes liquid cooling’s troubles worthwhile, and several companies are ready to fulfill those needs. Options include buying an air-cooled card and adding an expensive liquid-cooling “water block” or purchasing a card with the water block pre-attached, such as the GeForce GTX 285 Infinity Edition from Zotac.
Liquid-cooled graphics cards typically cost around $50 less than the sum of their parts (high-end water block plus a high-spec card), so the smart money for anyone looking to water cool is to buy these parts pre-assembled. Zotac adds one more reason to purchase its product by pre-overclocking its GPU and RAM to extra-high speeds, selling the card with a warranty that home overclockers typically must sacrifice. That also means that each GTX 285 Infinity Edition is hand-selected for its ability to support the rated speeds, while the purchaser of a reference-clocked card must rely on the luck of the draw to reach similar or greater speeds.
Overclockers aren’t the only market for liquid-cooled electronics, as similar methods have been used to address airflow constraints in densely packed servers. And let’s not forget home-theater and audio-studio applications where liquid cooling allows enormous passive radiators to suffice in situations that would have otherwise called for noisy high-speed fans. All of these markets share a common goal of increased cooling capacity at reduced use of local space and these are things that even non-overclocking performance enthusiasts can appreciate.
Source from www.tomshardware.com
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