Energy efficient pc recommendations?

[SgtSpoon]

Hi all,

I would like some recommendations for building a new energy-efficient pc. I will use it mostly for webbrowsing, some development work (visual studio, mssql server) and an occasional game. Gaming isn't all that important : for gaming, i use my xbox 360. Budget for this upgrade is a maximum of 500€, but for this amount, i only need :
- motherboard (required for new cpu types...)
- cpu ( currently my system has an Athlon 3500+. Quadcore would be nice, but it will also eat more power so i think i'm going to stick with 2 cores )
- 4Gb memory (my system currently has 2Gb of ram. do i add 2Gb of DDR2 ram, or do i loose the DDR2 and replace with DDR3?)
- my current 7800GTX is still ok for most games, so i don't think i'm going to replace it
- an SDD disc would be great for speed and power consumption, but i think i'm going to wait until i can get an 100Gb disc for 100€ (next year maybe?)

Components will be bought in belgium, and im not planning to overclock.

Brand preferences:
- AMD/Intel does not matter
- I have been using Asus for the past 15 years, and never had any problems with those boards.

What i would like to know is what components i would have to choose, if i want a good balance between performance, price and last but not least power consumption. I used to totally neglect the last criteria, but since my computer is always on, i'm going to pay some attention to it this time.

Suggestions welcome!

 

[MalVeauX]

Heya,

There isn't an energy efficient setup that you can build that will also allow modest gaming yet. Also, things like visual studio and mssql server enjoy heavy processors. And also, a Quadcore doesn't use more energy than a dualcore necessarily just because it has more cores. There's 45w single cores, 65w dual cores, and 95w quadcores. They're always coming down. And if you're talking AMD, they have QuietNCool on the motherboards which drop their volts and clocks to conserve energy. If you ever tested it or read about it, you'd see the Quadcore system dropping down to the energy levels of a Dualcore system when the extra juice is not needed. Also, the more memory sticks you use, the more energy that board will use (very slight amount, not worth really measuring, but hey, you mentioned energy efficiency). For your price range, SSD is out of the question really. The difference between a 5watt drive and a 7watt drive is minimal (even in a 24/7, 12 mo/year setting). Pennies difference for 24/7. So don't worry about this. Also, I would stress that you avoid going Atom (even the dualcore). They are low power CPU's, but their motherboards are not really yet, so you can build dualcore systems with similar wattage use with way more power (it's silly, until new motherboard chipsets are made for the Atom, they're really just not worth anything other than netbook use).

I would get a 620 Propus Quadcore and underclock/undervolt it and take the fan off and go fanless (just a heat sink). Or, get a Regor dualcore and do the same. Combine with the 780 series AMD chipset. Use only 2 sticks of RAM. Use only enough components that you need; every little thing takes power. I'm sure you can get this down to around 55watts during light use. But it has the power to deliver for you when you might need it thanks to being a decently clocked Quad.

Very best,

 

[piasabird]

Asus motherboards are not know for being energy efficient. I think an Intel brand MATX Motherboard would be a good bet for a motherboard that will use less power when in sleep mode, but I am just guessing. Never seen a report on this comparing various motherboards. I think what might be more important is the processor voltage requirements versus performance. The more cache used the higher the power consumption. Gigabyte also is another good brand for MATX motherboards at lower prices.

A lot depends on what kind of video ports you want to use and how much you want to spend on the motherboard. Also important is what kind of monitor you have or plan to use. If you have to have DVI or HDMI integrated ports, that limits your selection criteria. Also if you have a need for full 1080p integrated HD video that would also limit your choices. You have to narrow your selection criteria. If you can use a monitor with a VGA port then that gives you more selection. This can make a difference between selecting a $49 motherboard and a $120 motherboard.

Memory slots may also be an issue. If you want 4 memory slots that is an issue. If you can live with 2 memory slots that can probably lower your price.

If you add a video card that will significantly hurt energy efficiency.

For power consumption also look at newer LCD screens.

 

[Ken g6]

I'll start with some specs on my current system (that I'm typing from):

• CPU: Intel C2Q 9400
• MB: Gigabyte GA-G31M
• Memory: 2xG.Skill 1.8-1.9V 2GB DDR2 (4-4-4-12) (I picked these specifically for low voltage/high performance.)
• Generic 80+ 350W PSU
• Stock CPU cooler, with fan, plus two case fans, plus PSU fan (not much help with an 80+ PSU).

With one HDD, one optical drive (while not in use), I can undervolt to 0.96V while underclocking to 2GHz, and get only 65W on my Kill-A-Watt. That's quad-core, and under Distributed Computing load (see my sig!)

The most important things I've seen:
- PSU. Get the best 80 Plus rating you can.
- CPU. Get one with small features (45nm) that can underclock/undervolt well. Mine is limited to a minimum 6x multiplier; I don't know what the limits are on others. Here's a chart of clocks/watt at default speeds. If you go quad-core, limit your cache - there were different dies for C2Q, and my Q9400 is the smaller die.
- Video card. Video cards can use a lot of watts. Here's an interesting chart of TDP. Again, smaller feature size (40nm) is better. I've been thinking about getting a GT 240, which uses 10 watts less than your current card, but is far more powerful! There are some that use even less power, but some, such as the GeForce 210, are less powerful than your current card.

 

[RebateMonger]

The lowest-power PC is the one that's turned off or is in sleep or hibernation.

As noted, as soon as you add a separate video card, you up power consumption by maybe 50%. If you can live with three-year-old games, I'd get (using Intel example, since I know nothing about AMD) a 45nm Dual Core CPU and a built-in 4500HD video chip. That'll be in the 50- to 65-Watt power consumption region.

If you want less than that, an Atom-based system can go down to around 35 Watts, but you'll lose CPU power and the motherboards have other limitations that reduce flexibility.

 

[lxskllr]

The lowest-power PC is the one that's turned off or is in sleep or hibernation.

Why not build an energy muncher, but utilize sleep with the O/S. I've found it to be very reliable in Vista and Win7, and depending on hardware can work very well in Linux. Keep in mind, energy consumption is "free" in the winter. You're making heat which you would be doing anyway. I keep my PCs on 24/7 in the winter, and I've also started folding to work the processor and generate more heat. In warm weather I put the PCs to sleep, and they wake up in seconds.

 

[M0RPH]

Why not build an energy muncher, but utilize sleep with the O/S.

Because you can also utilize sleep with the energy-efficient system just as well?

Keep in mind, energy consumption is "free" in the winter. You're making heat which you would be doing anyway. I keep my PCs on 24/7 in the winter, and I've also started folding to work the processor and generate more heat. In warm weather I put the PCs to sleep, and they wake up in seconds.

I have a feeling that's a very inefficient way to generate heat.

 

[lxskllr]

Because you can also utilize sleep with the energy-efficient system just as well?

With an energy muncher you get the benefit of speedy computing with minimal extra energy use. I'm not saying be stupid about it. An energy efficient PSU still makes sense, but a fast CPU is more enjoyable to use, and will only cost a dollar or 2 per month extra, if that.

I have a feeling that's a very inefficient way to generate heat.

All energy use creates heat in the end. You might as well do some good with the consumption instead of just making yourself warm. I dropped 2°F on my thermostat(55F down from 57F), and fold on my computers to generate extra heat.

 

[SgtSpoon]

Thanx for the suggestions guys, this really helps!

 

[theevilsharpie]

What i would like to know is what components i would have to choose, if i want a good balance between performance, price and last but not least power consumption. I used to totally neglect the last criteria, but since my computer is always on, i'm going to pay some attention to it this time.

Suggestions welcome!

Processor: Intel without question. Their chips get much better performance for the same or lower power utilization.

Motherboard: Avoid high-end gaming motherboards, as these tend to be very power hungry. You can get an idea of the power consumption of these boards by looking at the size of the heatsinks on the northbridge and southbridge. I would go with Intel or some other "professional" non-gamer mobo manufacturer. Enthusiast board mfgs tend to focus on raw performance and overclocking options instead of making sure that processor power features work properly.

RAM: Avoid low-latency enthusiast RAM or any RAM that requires unusually high voltages. DDR3 uses slightly less energy than DDR2.

Video: High-end cards are out, obviously. Wikipedia has a list of the TDP of various cards, but as with motherboards, the size of the cooler is usually a good indication of the power requirements.

Disk: SSD for OS or high-performance scratch space. WD Green series for bulk storage.

 

[SgtSpoon]

So far, i have found a nearby shop that has a huge list of power supplies with lots of brands, and some of them have the 80 Plus rating. I can get my hands on a Corsair VX 450W psu for a good price, and i've read good reviews of it. But is 450W enough to drive a machine with a quadcore, 2 or 3 discs, some usb devices? Also, i'm going to consider onboard-vga, but i want the PSU to be able to handle a GPU if i ever change my mind.

About cpu's, im considering these:

- Q8400S (LOW POWER) : Quadcore with 65W TDP, 200€
( link : http://processorfinder.intel.com/details.aspx?sSpec=SLGT7 )
- E8400 : dualcore with 65W TDP, 150€
- AMD Phenom 2 X4 905e : Quadcore with 65 TDP, only 150€
( link : http://products.amd.com/en-us/DesktopCPUDetail.aspx?id=557 )

So basically, 3 cpu's with 65W TDP. 150€ gets me a dual intel or a quad amd, and 200€ gets me a quad intel. Undervolting is something i will definitely try: i've seen reviews where it makes a difference of 10W.

As the system disk, i will probably buy a WD "Green" disk for now, but i do plan to swap it out for an SSD when they become affordable (at least 1GB/&#8364

 

[rudder]

The lowest-power PC is the one that's turned off or is in sleep or hibernation.

Exactly. I am more concerned with performance than energy savings. Why skimp on a video card or cpu because it uses to much juice?

I have a core i5, 650watt 80 plus certified PSU, and throw it into sleep mode or shut it down for the evening. Recovering from sleep is quick and painless.

If you do more surfing than gaming... get an intel atom/motherboard combo for $79. Throw in a stick of ram and a hard drive and you dont have to worry about your electric bill.

 

[MalVeauX]

Heya,

Really, efficiency of the energy relating to the cost of operation is only truly significant in a 24/7, always on, environment. Just look at how your utility company calculates your cost of usage of electricity. It's usually a flat rate for the service and your first 250 or so kWh (kilowatt hours) at a set price. Then you pay by the kilowatt hour (kWh) above that amount in brackets (example, $0.06 per kWh above 250 up to 500 kWh; $0.10 per kWh above 500 kWh usage up to 750 kWh, etc). That's not the same for everyone, it's just to give you an example of how it trends.

My average use per month is about 550 kWh and it costs me about $70 a month for that (all my appliances, lights, AC/Heat, etc). I have lots of computers and some of them run 24/7, so I care about energy costs so that I can keep it down. My bill is relatively low compared to a lot of folk in my area (Florida). If this were a 5 bedroom house, this bill would be like $400 for example, to cool it.

Anyhow, I always take into account my energy use by it's cost in the end. You can calculate it yourself. I have a watt meter that I use to measure how many watts a device (or group of devices) pull from the outlet. I use that to calculate how many watts I use per hour, which when converted, gives me my kWh (kilowatt hour) which I then know the cost per kWh through my utility bill. I can determine what it costs me per month to run a machine based on usage.

So for example, my primary machine uses a lot of energy. It's an overclocked 955 at 3.8Ghz, lots of fans, several drives, a power hungry 8800GT that is also overclocked, etc. At load, it easily breaks 500+ watts (but usually is never under full load). I only use this machine about 6~8 hours a day, every day. But it's not always at full load. A lot of time, it's at idle or only under minimal load, and it only reports 115~120 watts during these times. So let's look at an average, like 300watts for example, 8 hours a day, every day for a month at $0.10 per kWh to calculate it on the higher end of things. That would be (300watts)(8hoursperday)(1/1000 to convert to kWh)(31days to equal a month)($0.10 per kWh)=$7.44 a month to do that. That's pretty heavy use though, 8 hours a day every day? Not everyone does that. Some do more! Many do much less. And that's assuming 300watts. Most people will not use that all 8 hours of every day like that. So this is a huge overestimation of cost. My cost is likely closer to $2~$3 a month for usage on this machine because it's way more often being lightly used, at near idle, and not at full load.

But my server is on 24/7 for example. It pulls 55 watts usually with all its drives, constantly on, and on a UPS backup so that it doesn't get interrupted by a brown out. To calculate it's cost: (55watts)(1/1000 to convert to kWh)(24 hours per day)(31 days per month)($0.10 per kWh)=$4 a month essentially. That's assuming the higher cost though. Mine is actually $0.06 per kWh at my usage level, so it's actually $2.4 a month for my server to run as it does. And my server is actually inefficient. You can make smaller wattage usage computers. And my server is a 2.9ghz 65watt dualcore (regor) on a gigabyte 785 amd board with 5 drives, optical, floppy, two ram sticks (more sticks actually uses more energy), running two webcams for surveillance 24/7 (they are 2.5watts each), with my software running, I have an FTP server, active webcam software that records/takes stills when there's motion, but 24/7 monitors, uTorrent, the drives are all WD greens except the OS drive which is a WD Blue. It's on a 400watt Corsair PSU. Quiet & Cool lowers the volt/clock a lot and it stays idling at a tiny value. The machine could crank up and do heavy duty work being a powerful dualcore, but it doesn't need to. It's running Win 7, not some server OS. You don't need specific stuff to make a server energy efficient while having a powerful machine (not some crippled junk). I did this route because when I change machines, this machine is still useful for something besides serving (add a GPU and it's a gaming machine, literally, which I can sell or give to someone). You can take nearly any energy hog and change settings and how it uses energy and make it a very small foot print on your power bill.

-- So instead of trying to just make the machine generically energy efficient, focus on making it efficient but able to perform to your needs based on how often you're using it, or how often it's on and drawing power. You can then make a better machine for your needs. If it's not in a 24/7 always on environment, you really, really don't need to stress mass efficiency to the point of basically running a crippled machine as your primary machine.

If you want to really worry about efficiency of parts and power usage, a Folder is someone that worries about this. Because having a machine that draws over 400+ watts 24/7 all the time, folding, is going to put a huge stamp on an electric bill.

If you're not using it 24/7, don't worry about it.

Literally sit down and look how often you use the machine in a month in hours (you may only use it 4~6 hours, only some days out of the week). You will not notice this on your bill.

Very best,

 

[lxskllr]

Exactly. I am more concerned with performance than energy savings. Why skimp on a video card or cpu because it uses to much juice?

I have a core i5, 650watt 80 plus certified PSU, and throw it into sleep mode or shut it down for the evening. Recovering from sleep is quick and painless.

If you do more surfing than gaming... get an intel atom/motherboard combo for $79. Throw in a stick of ram and a hard drive and you dont have to worry about your electric bill.

Ya know, that would be a cool setup. Use a mini ITX rig piggybacked on a full blown computer. Use CF cards for the drives on the ITX, and it would fit in a tiny case. You could use that for pedestrian tasks, and wake up the real machine when heavy computing needs to be done. Run them both to the same monitor, and the extra space and expense would be minimal.

 

[kalrith]

I leave my HTPC on 24/7, so energy efficiency was a big deal to me. Here's what I built:

Abit AN-M2 motherboard
AMD retail BE-2300 (1.9 GHz dual-core)
9500GT video card
4GB (2x2GB) DDR2 RAM
WD10EADS hdd
Hauppauge HVR-2250 tuner card
​

I use CrystalCPUID to undervolt and underclock the processor at idle. I specifically chose that mobo because the silentpcreview forums praised its ability to undervolt.

It pulls about 55W from the wall (according to my Kill-A-Watt) at idle after overclocking it. I overclocked the cpu to 2.66 GHz, but it runs at 1.12 GHz at idle. I think it pulls about 120W from the wall at full load of both the cpu and gpu, but it doesn't ever hit that from normal usage.

I really need to replace the psu, because I have an inefficient one (it was FAR). However, it would take about 10-15 years to recoup the costs of an efficient psu from energy savings. I spend about $30 per year to run the PC 24/7 at idle. I would save about $1/year with an Earthwatts 380, $4/year with a Sparkle 250W, and $6/year with a PicoPSU 120 (most-efficient PSU). Those power supplies cost about $25, $50, and $90, respectively. While they might be better for the environment, they don't make financial sense.

I don't use it for games, but for general and HTPC usage it runs flawlessly.

 

[JackMDS]

Totaly Off by the power strip is 0 Watt.

Power consumption when it is ATX Off, consumes 1-3 watt to keep the Network card and PSU ready to start, and it is the same for Hibernation.

A well tunes sleep mode may use 5-10 Watts.

The rest is up to what the computer is used to and personal habits.

Exampe,

If you do more surfing than gaming... get an intel atom/motherboard combo for $79. Throw in a stick of ram and a hard drive and you dont have to worry about your electric bill.

I.e. Use the above as the workstation, and switch On the "Gaming Hog" only when you play.

.

 

[yh125d]

I have a feeling that's a very inefficient way to generate heat.

It will be roughly however efficient your PSU is. Say your PSU is 85% eff, and you draw 350w at the wall. Thats 297.5w going into the PC. Not quite all will become heat, say - 20w for the energy transferred into motion (HD disks/fans) and you have roughly a 275w heater under your desk. I don't know how efficient central heating is or little supplemental heaters are, but an ~80% eff computer heater doesn't sound that bad

 

[RebateMonger]

In the end, ALL of the energy going into the PC ends up as heat. Including the loss in the power supply, the light coming out of the monitor, and the power used to keep the fans spinning.

 

[yh125d]

Yeah what's lost as eff in the PSU goes to heat, missed that, but the light and motion do not end up as thermal energy