Building an Energy Efficient, Always-On PC?

An anonymous reader asks: "Like many readers, I find it necessary to leave my home PC running 24/7, for things like web or FTP servers, BitTorrent, or simply to make sure I don't miss any messages on IRC or my instant messaging client. It has been about 3 years since I built my current PC, and keeping it running all the time uses a lot of juice. With my next PC, I would like to do what I can to keep the power-consumption to a minimum, without sacrificing processing power or other features. What should I look for when choosing components for my PC, and what other ways are there to keep the power consumption down?"

Don't forget the monitor

[Pyrex5000]

Using an LCD monitor instead of a CRT will drastically cut your power usage. Turning off the monitor while not at your computer will help as well, instead of just letting the screensaver run. The monitor can consume more power than the PC itself.

Get a vhost

[Mr.Ned]

A good option is to get a cheap virtual host. You get root, install what you like, run what you like, and it uses less power - none of yours - because there are several mostly-idle virtual machines on the same host.

Disk space is relatively expensive, and this may not be an option for you if by 'BitTorrent' you mean 'fill up my 500GB hard drive'.

Re:Dont bother.

[bcrowell]

Well, the OP didn't say whether he was interested in low power in order to save on his electric bill, or for ecological reasons, or both. But you're right, it's not necessarily ecologically sensible to buy new hardware. In my area, the garbage company runs a disposal site for hazardous household waste, and when you go there, you see big stacks of computers. They have a program where if you ask, you can take computer hardware for free. For someone who really wants to do a favor to Mother Earth, it might be a very sensible way to pick up a case, a CD drive, and a hard disk. If there isn't anything like that in your area, chances are you can get those parts pretty darn easily at a garage sale. I picked up a really nice CRT recently at a garage sale for $10. I put it on a machine at the school where I teach that doesn't get used very often, so the electricity isn't a big issue. It sure beats dumping that same CRT in a landfill.

Two boxes is the way to go

[toddestan]

It sounds like you leave your computer on all the time, and use it for a variety of tasks, and you are looking for a machine that can do all of that while being easy on the electric bill. This hard to do, as things like high powered CPU's, high end video cards, and lots of storage tend to not be low power. I suggest you get two computers. Get a low power machine, either an old laptop or a P3 and offload all the tasks like the FTP server and the bittorrent duties to this machine, and leave it on 24/7. Old laptops work great for this, as they are built for low power and have a built in UPS. P3 systems also work well, many ex-corporate P3 class systems are quiet, low power, easy to work on, and dirt cheap. Then you get a high power machine, and only have it powered up when you need it. You can have the two computers set up next to each other, and use Synergy [sourceforge.net] to run your IM/IRC on the 24/7 computer while doing whatever on the high end machine at the same time.

If you still must have it all in one desktop machine, one way to cut the power usage if you like lots of storage is to try to only have 1 HDD in the computer, and put the rest on USB/Firewire harddrives which you can then shut off when you don't need them.

Re:Another mislead AMD/Intel power comparison.

[dnorf87]

AMD and Intel rate their processors TDP (Thermal Design Power) differently. Intel rates their TDP by typical usage, while AMD gives the maximum the chip is capable of consuming under severe conditions. Check out the TDP of comparable Intel and AMD processors, then get back to me on that. I think AMD's power consumption is pretty impressive if you include the fact that they have an integrated memory controller, and how they are usually a process behind Intel (90nm AMD vs. 65nm Intel). At least AMD has new, very energy efficient 65nm processors out. Much better :)

Re:Low power consumption CPU is needed

[aliquis]

For that price he could probably afford loads of electricity.

Laptop

[fozzmeister]

Is probably the most mature low power solution, other alternatives are things like MicroATX etc.

Re:Don't forget the monitor

[Seumas]

I have found that the best way to conserve power and reduce your electricity bill is to buy a PS3 and then let that stupid folding@home app run full time so you can do a bunch of work for some corporations via Stanford and pay for the electricity it consumes as well. Nothing says cost savings like running a power-hungry heater like the PS3 full time! And even better, make sure to keep your television on so you can watch the fancy folding screen saver!

Re:Don't forget the monitor

[compwizrd]

I just swapped out a 22" CRT to a 24" LCD panel, and my usage at the wall went from 210W to 150W