I read an advertisement for a hot new computer. It boasts an overclocked, quad core, liquid cooled processor at the helm – all for the cost of a mere $5000. As an engineer, my first thought was that’s a lot of power in one computer. My second thought was, how much electrical power does this monster computer consume? In a world focused upon greener technology and carbon footprints, how did we get to the point where a personal computer needs to be supplied with 1000 watts of power?

First, I should offer disclosure so you know where I’m coming from. I don’t work for an oil, energy, or computer company. I drive a Prius; I believe we need to reduce our dependency on oil, reduce pollution and carbon dioxide emission. But, I’m by no means a tree-hugger. I am an electrical engineer so I do know something about computers.

Let’s take a historical look at the desktop computer from the point of view of capabilities, speed, and CPU power consumption. (CPU stands for Central Processing Unit, the chip that is the “brain” of the computer.) I purchased my first computer, an Apple II, back in 1982. It had a CPU that ran at a clock speed of 1 Megahertz (MHz). The clock speed of a CPU is a measure of how many arithmetic instructions it can perform per second. One MHz translates into one million instructions per second. Today’s computers are measured in Gigahertz (GHz). One GHz translates to one billion instructions per second, or 1000 times faster than a one MHz.

While I’m at it, I should say that my Apple II had a whopping 64 K bytes of RAM and a floppy disk that could hold a few hundred K bytes of data. (K stands for thousand). Today’s computer memories, measured in gigabytes, have 10,000 times as much memory and the disk drive sizes have increased by as an even larger proportion.

My one MHz, 64 K Apple II could handle word processing, spreadsheet, computer programming languages, and many programs similar to what we use today. It may not have performed these functions quite as quickly, or with today’s wiz-bang graphics and features. But do we really have 1000 times the functionality or performance as we had in 1982? (As a side note, my Apple II powered up faster than today’s computers do.)

If I were a conspiracy theorist, I might have to propose that there has been a conspiracy between the CPU vendors, the memory chip vendors, and the software vendors. Each time the CPU vendors come out with faster, more capable CPUs and the memory chip vendors cram more space onto their memory chips, the software manufacturers write software that sucks up all the newly available resources. We buy a computer. Then we buy software. Before too long, we have to buy a faster computer because the software starts to bog down the computer. Then the software manufacturers release newer versions of software. The cycle seems to be endless.

Let’s get back to the $5000 computer. The advertisement said that it is overclocked as if that is a good thing. Computer chips are rated by their manufacturers with maximum clock speeds. Under a specified set of conditions, including operating temperature range, the manufacturer states that a chip can run at a specified maximum speed. In some engineering circles, overclocking is a taboo practice because it means that you are clocking the CPU at a speed faster than that recommended by the manufacturer. If you can guarantee the right operating conditions (such as keeping the CPU cool), perhaps you can get away with overclocking as long as you test the heck out of your overclocked product before selling it.

What does this all have to do with my aforementioned environmentally unfriendly 1000 watt power consumption of this quad core, overclocked, liquid cooled computer? The faster you clock a chip, the more power it consumes. That goes not only for the CPU chip, but other chips inside the computer. It just happens that the CPU is clocked at the highest speed. Furthermore, this monster computer has a quad core CPU, which means that it has four CPUs built into a single processor. Power consumption also increases with the number of cores. So not only does this chip consume more power due to overclocking, it also consumes nearly four times the power as a single-core CPU running at the same speed.

And, to add insult to injury, the consumer is expected to pay not only for an expensive quad-core CPU, not only for the electricity to power this monster, but also for the high-tech liquid cooling that is required to cool the monster CPU. Power consumption results in heat, and you can’t run the CPU quickly unless it stays cool. The computer manufacturer is spinning the liquid cooling as a cool feature – be the first on your block to have a liquid cooled computer. Brilliant marketing? Are you going to buy a $5000 computer? Do you really need that kind of power? Not I.

To be perfectly fair, I should note that features are built into the CPUs so that they consume far less power when they are idle. But an idle condition may not be as frequent as you think. Does your virus scanner run every night? Once a week? Does it run for an hour? Two hours? That’s not idle time.

A few more statistics for comparison and I’ll get off my soap box. The quad-core CPU consumes 130 watts by itself. A similar single core CPU consumes 30 watts. You know how much a 100 watt light bulb consumes, I hope. A CPU in a cell phone or PDA consumes less than one watt. A television consumes a few hundred watts. Yes, the bigger the screen, the more power it consumes.

But the TV leads me to my parting thoughts. How about all our home electronics? The TV, the cable converter, the VCR, the DVD player, the stereo equipment. Most modern home electronics consume power whether they are powered on (active) or powered off (standby). Some have built-in clocks. Equipment that includes remote control must have circuitry that receives the remote control’s infrared signal. This circuitry is on 24 hours a day, 7 days a week. Some equipment requires a watt or two of standby power. But some televisions burn 25 watts or more when powered OFF! By default, digital video recorders (DVRs) are never truly in standby. They are always recording the current TV channel, thereby consuming far more than a trickle of standby power.