Hello,

I wanna buy the proper components for a machine that doesn't consume much energy. Priorities are:

1. Energy saving
2. Performance
3. Silence
4. Price

This is my list (so far):

• Motherboard with onboard graphics like the 780g/790gx, but nvidia (which one?)
• Enermax Pro 82 385W (is that ok?)
• Katana 3 CPU Cooler
• Scythe "KAMA FLEX" 120 mm Silent Case Fan
• 4GB Ram
• Samsung EcoGreen F2 500GB, SATA II (HD502HI)

What do you think/recommend?

Hi, welcome to LQ!

Interesting question; I'm afraid that for the most
part high performance & power saving are almost mutually
exclusive (that's a slight exaggeration/over-simplification,
but you get the drift).

What are the computational requirements, what kind of
graphics use do you expect on the machine you're building?


Cheers,
Tink

Graphics should be good enough for blueray, google earth, compiz. So 3D isn't the most important issue. I'm no hardcore gamer.
...
so let's downgrade 'performance' to number 3. Need at least enough power to run a vm.

Linux Format did a recent article on Building a Myth TV Box (April 2009 Issue 117)

The board they recommended was the Asus P5N7A-VM

The connections on this board and the integrated GPU make it a pretty obvious choice for a Multimedia PC. .

Plenty of reviews out there on this board, I'm just suggesting it as another option, since I have not used one of these.... Yet. Although all of those video connection options are very compelling..


I could be off the mark, but your initial post sounded like that is what you were shooting for.

PSU

A stronger PSU at a given output will not use more current than a weaker PSU at the same output. However, the stronger will waste less current as heat and last much longer.

Green is a long term investment and may be expensive at first.

What CPU do you have in mind, or should I ask, why so many cores?

In addition, think about your choice of a cabinet for its air flow qualities.

Think this one would be a good choice: AMD Athlon X2 5050e / 2.6 GHz Energy Efficient

Depends where your preferences lie. As with above, you mention performance but haven't suggested what performance you would like. Getting 1.2GHz out of a small energy efficient PC that runs at around 20watts would be very good indeed, but not knowing if this is too little I wouldn't like to recommend it.

For example, would you rather have it running at a lower wattage at the sacrifice of performance, or would you be happy for it to run at, say 180-200watts?

180-200W would be ok I guess.
I'd like to run a vm, watch video, run google earth and compiz beside internet/mail.

What's the VM gonna do, will you want it to do
heavy stuff while you watch videos?


Cheers,
Tink

heavy stuff?
don't know.
I don't think so.

In that case - won't an Intel Atom or even a Via C3 nehemia do? :}

They do video smoothly, and if the VM won't be used for gaming but
maybe just for Word or Excel I don't think that the CPU needs to
be all that grunty. Just my 2 cents.


Cheers,
Tink

I suggest stick with either Hitachi or Western Digital for hard drives. They are more reliable than Samsung.

If you are going to use VMware, AMD processors is best for this compared to Intel's Core 2 Duo processors. Sure Intel i7 processor could be used, but they are costly.

I suggest do not look at the TDP of the processor because this tells you nothing for an overall consumption. I suggest pick something like a Phenom II X3 or X4 then use cpufreqd to adjust the speed of the processor to provide good power savings. If you setup cpufreqd properly, you should not notice any hesitation. To save power when not in use, you can setup suspend to RAM.

Using Compiz or Beryl will hurt your goal for the lowest power consumption. It also affects stability and reliability. Third Compiz decreases the ability to use stream processing from the video card to aid in decoding videos that uses MPEG-2, H.264, and WMV3/9. At this time on nVidia has good core API that they provided for developers to use in media players.

The Scythe "KAMA FLEX" may not be the most silent fan that provides good performance. Depending on the case, you should look at the pressure of the fan provides instead of CFM. A Cooljag Everflow 120 mm X 25 mm (R121225BU) seems good because it has high pressure, high CFM, and its highest audible noise is 39.5 dB.

Power supplies from Seasonic is more efficient at that wattage range.

FYI, a "green" computer does not always mean low power. It means something else. If you want a green computer, look for hardware components with RoHS. Also find out how far the components are traveling from the factory and then to you.

thorkelljarl, the term green is not expensive. Actually it is the cheapest way. Probably electronics is the hardest way to be green because RoHS does not allow certain metals to be used which then requires more energy.

Personally, I think you're wasting your time. For what you want to do and the power you think is reasonable, you may as well just buy a stock PC like a Dell or HP.

What you are after is shaving off a few watts from a normally powered PC. It would be like trying to get an extra 0.2 miles to the gallon out of a car that already did 65 to the gallon.

Sure, its better, but not worth all the effort.

Further along this point, I guess I'll be "that guy" that points out that how you have your power preferences set and how you regulate the usage (time in sleep mode, time actually off) will probably have a much greater impact than anything else.