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Scotty, We Need More Power!

The Graphics State of the Union

Here is a picture of a new PSU from Enermax that can produce 1100 W (peak).

Without any changes, all of this means we will need bigger power supplies. Talking to the power supply manufactures and system integrators, the new power supply generations are being targeted to deliver over 1,000 W (or 1 kW).

The PC Power & Cooling 1 kW power supplies are doing great in our labs. They deliver solid power across all of the rails, and they are great for the high-end test platforms we run. Everything about them is big - that also includes cost, as such a power beast could easily cost you $300 and more (the units powering our test benches are in the $400 range). To run a system with midrange dual graphics you should have at least a 500 W power supply to be on the safe side. Can you get by with less ? Perhaps you can, but why take the risk ? Spending a little more on a PSU is better than a fried CPU or other sensitive component, or jeopardizing system stability due to unreliable peak power.

Let me give you an example of needing more power. AMD removed the Antec TruePower 550 power supplies out of its game test lab and went for higher output units. Were the Antec power supplies bad ? The units we had in for testing did well and survived our stress test scenario, so the answer must be "no." It was simply discovered that while testing ATI and Nvidia cards in the AMD labs some of the systems failed, as they could not handle the dynamic load that 3D rendering can cause. One picosecond to the next, the power demand in a graphics core fluctuates. This can blow a power supply or simply cause it to fail temporarily, turning the system off.

This brings me to another point. I know of one case where a person in Florida purchased a high-end PC from a well known PC maker. He got the system and plugged it into a socket in his den. He pushed the system power button, but it would not turn on. After some time on the phone and a visit to a local computer store, the guy solved the problem. It seems that his brand new house was built with devices called Arc Fault Circuit Interrupters (AFCI) in all rooms. When the system drew its first breath it tripped the interrupter ; only when it was not on a protected circuit did the unit turn on.

In 2002 there was an addition to the National Electrical Code (NEC section 210.12) that requires 125 V single phase 15 A and 20 A outlets in residential bedrooms to include AFCIs. Not all states are enforcing this via legislation, but as most things in life it is only a matter of time until the code makes its way to you.

Why should you be concerned ? Unlike ground fault circuit interrupters (GFCI) you find in a bathroom to help prevent electrocution, AFCIs help to prevent fires by detecting a jump (arc) from one insulated carrier to another and then cut the power. (A good article on AFCI explanations can be found here. The problem occurs when it trips because of a series arc (inside a single wire) - when there is a surge in the power requirement, or if a power cord is kinked and straightened out again. Like the man in Florida found out, his new top-notch system could not run because of this power legislation, which leads me to ask one question : why do computer components have to draw so much power ?

Sure, we like the systems and graphics horsepower, but the cost of a high-end power supply for a macho machine is $100 for a minimum like the Antec TruePower 550. When AMD had to replace theirs for higher-end units, they were now looking at $200 and $300 price tags. Kilowatt power supplies coming to market means another increase to $300 to $500.

Just to add insult to injury, we have Microsoft Vista with the Areo Glass experience. Instead of only running the 2D section of the graphics core (which accounts to 4% of a high-end graphics core today), the 3D’ed Windows Vista will run the other 96% all the time. Granted, there will be power saving features to turn off parts of the core that aren’t needed for picoseconds at a time, but no matter how you look at it, Windows will be running it more of the time than before.

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