Do you consider power consumption when choosing a CPU?

Is power consumption even a factor. I think most people will choose a CPU based on a combination of OC & price?
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  1. Nope - Not at all.

    For business users running large numbers of machines for 24 hours a day, 7 days a week, 365 1/4 days a year, and trying to keep their power bills down, sure. Especially if they can publish press release containing a steaming pile saying they 'saved blah de blah amount of greenhouse gasses by changing....' <barf> while they're doing it.


    But for gamers/home users?? <looks at CPU... Looks at 8800GTX.... giggles> Power consumption matters not. Heat production?? Oh Yeah. But 'tron usage?? Pulheeeze... Just shut the thing off when you're done using it.
  2. Well isn't lower power consumption parallel to lower heat production? I'm all for less heat for the the same performance.
  3. I voted yes, but my vote was based on process more than TDP (although, they tend to scale together). For instance, I would much rather buy a 45nm chip that can run at similar frequencies using less overall power than any other process which might run a little "faster".
  4. Absolutley True, they are most definitely related. Efficient designs generally use less power and efficient designs are generally faster. So we do look at power consumption as a sign of efficient design. But the reason we look isn't how many 'trons it's using - it's the heat~performance ratio.

    I know real world physics don't work like this, but by way of example: If a processor was 10% faster for twice the power requirement, yet magically produced half the heat!?!? Home/Gaming Enthusiasts would buy it! Conversely, if two processors used the same power and were otherwise equivalent, the cooler-running one gets the nod.
  5. Sure of course I consider the power consumption factor. Because like UncleDave said, more power generally means more heat production. And more heat production has the potential to raise the room temperature therefore making your AC run more often to bring down the temperature to your desired setting. For someone like me who lives in Miami, FL, the AC usage plays a big role in the electric bill. So building a PC that has great performance and low power consumption, which therefore produces less heat, is something I aim to do.
  6. andytg7 said:
    Sure of course I consider the power consumption factor. Because like UncleDave said, more power generally means more heat production. And more heat production has the potential to raise the room temperature therefore making your AC run more often to bring down the temperature to your desired setting. For someone like me who lives in Miami, FL, the AC usage plays a big role in the electric bill. So building a PC that has great performance and low power consumption, which therefore produces less heat, is something I aim to do.


    For someone like me who lives in the Pacific Northwest, heat is no problem at all.
  7. Well, it's a factor. But if we were all THAT concerned with heat, we would be using VIA CPU's and embedded graphics and Linux.
  8. I leave my pc on all the time in winter and the sweet noise of the fan puts me to sleep.
  9. UncleDave said:
    Is power consumption even a factor. I think most people will choose a CPU based on a combination of OC & price?


    Definitely Power Usage is an important factor.
    More Power Usage = More Cooling Requirements = More Noise or Very Very Expensive Silent Options.

    Right now my system is Highly OC'd and very quite with a mid-level after market HS & Fan.
    I can OC another 200Mhz quite easily, but that introduces noise.
    Who wants that when you cant tell the extra 200Mhz.

    If my CPU was a Hot Chip, I would be hearing lots of noise all of the time.

    In my case, it's more important than most since I have 4 systems running in my room.
  10. Not for a gaming box but yes for a HTPC or home server or NAS type device tht stays on 24/7.
  11. For a CPU, power consumption IS heat. There's nowhere else for the energy to go. So for my HTPC this is especially important. I just wish my mobo supported a more efficient CPU.
  12. Since socks mentioned it first....

    drysocks said:
    Well isn't lower power consumption parallel to lower heat production? I'm all for less heat for the the same performance.


    I must admit that I didn't think of the basic power = heat equation :non: . My gut still tells me that people don't buy chips based on power consumption. When people overclock they will always mostly occasionally sometimes look at improving the stock cooling, but that is to ensure that their chips don't Chernobyl, this is only heat management, I would argue that power consumption as a consideration goes out of the window as soon as you start to overclock. As the zenmaster says he is worried about managing heat and noise NOT power consumption.

    I agree 100% with Scotteq

    p.s. At the risk of Trolling :bounce: - I also wonder how much, if any, after market coolers can increase power consumption?
  13. Hmmm, I didn't think that was trolling. If the concern is heat, it's a valid question. They almost all have fans though, so I doubt there's much difference at stock.

    Some people like to oc to the last possible MHz, and I'm sure they don't give a congressman's butt about power consumption. As Reynod points out though, to many others it will matter.
    Personally, having replaced all my bulbs with CFLs years ago, I like knowing my power bill is low. I won't give up a required or expected level of performance, but otherwise yes, the power usage will occur to me as I'm making my choices.

    Oh yes, and I also agree with Scotteq.
  14. UncleDave said:
    Is power consumption even a factor. I think most people will choose a CPU based on a combination of OC & price?

    For me power consumption is a factor, but a CPU is one of many factors. Basically if your PC is on an average of 8 hrs/day, 1 wasted watt is $0.28/yr (if your $0.10/KwHr). 24/7 is around $0.85/KwHr

    As you can see, it takes a fair amount of wasted watts for it to make much of a difference annually, but it does make a difference. Let's say your machine uses 100 watts more than it has to for the performance you really need to be happy. That's about $85 a year your machine costs extra (not including the price of hardware).

    That said, I'd say most people waste more power on their graphics processor. I don't understand why they haven't made them use about 10W for standard 2D stuff.

    John
  15. To me, power consumption on a desktop with a single CPU is not a factor I take into consideration.

    If I had a farm of servers, then possibly.

    i think the point of power consumption when selling to the desktop gaming market is a bunch of Al Gorish BS and carries no weight at least in my decision making process.

    If I can;t pay my electric bill to begin with, what the hell would I be buying a quadcore platform with sli/crossfire for?
  16. Well.. don't forget guys, that its not just the CPU. For example, what video card you run:

    Again, my dad's E4300 uses around 107-109watts idle (@2.4ghz) using 7300GT. My system (E4400@3ghz) is very similar to his, but I run the 8800GTS 320mb card. It idles at 170Watts (I did add a HD TV card to my system).

    So when I'm running folding on both cores, my system uses 207-210 watts, and thats without the GPU running or doing anything at... all. :cry:

    So all my power savings is pretty much shot from wanting a good GPU.

    I use a P3-kil-o-watt meter, btw. With both my new and old system running off UPS, my total system drains 497-510watts, adding around another $40 bucks to the electric bill.
  17. Of course it matters.

    Obviously more heat also means louder fans, as well as a higher electricity bill from your PC *and* the air conditioner during summer. It also has a knock on affect on your PSU purchase - a lower power chip can get away with a cheaper PSU.

    Most overclockers actually DO care about power consumption figures when choosing a CPU - just not the way most 'normal' (non OC) people think about it. Overclockers will always prefer a lower TDP, if possible, to maximise their chances of a big overclock. It gives them more 'thermal leeway'. Why do you think everyone prefers 95W G0 Q6600s over 105W B3 Q6600s? 10W ain't hardly gonna make you broke on the electricity bill, but 10W less may mean a 100MHz higher overclock.
  18. Grimmy said:
    Well.. don't forget guys, that its not just the CPU. For example, what video card you run:

    Again, my dad's E4300 uses around 107-109watts idle (@2.4ghz) using 7300GT. My system (E4400@3ghz) is very similar to his, but I run the 8800GTS 320mb card. It idles at 170Watts (I did add a HD TV card to my system).

    So when I'm running folding on both cores, my system uses 207-210 watts, and thats without the GPU running or doing anything at... all. :cry:


    I have a similar system, and I observed that as well (although I didn't actually measure the wattage of my PC, I knew my 8800GTS 320 was chewing up the most power). My solution? UNDERCLOCK it for 2D / desktop stuff!

    The default clocks are: 513c/792m
    My 'custom' 2D clocks: 111c/155m

    Yes, I have underclocked my 8800GTS 320 about 500% under stock speeds... it will not go any lower or I get graphical corruption on the desktop. :p I'm not sure exactly how much power it saves but I would assume a fair amount, since temps drop about 10c over stock.

    Btw, I use ATI Tool to make custom clockspeed profiles depending on usage. When I fire up a game, the card is automatically overclocked to 660c/1100m. When I quit the game it reverts back to 111c/155m. Talk about from one extreme to another huh. :lol:
  19. I did underclock the GPU. It only lowered it down to about 13watts.

    Although I really don't want to keep switching it back and forth when I do want to play games. Just don't know why my 8800GTS needs to consume about 60watts more at idle to begin with. Its doing nothing more then what my old 6800GS (agp) card did when just viewing 2D desktop... :cry:
  20. Grimmy said:
    I did underclock the GPU. It only lowered it down to about 13watts.

    Although I really don't want to keep switching it back and forth when I do want to play games. Just don't know why my 8800GTS needs to consume about 60watts more at idle to begin with. Its doing nothing more then what my old 6800GS (agp) card did when just viewing 2D desktop... :cry:


    How far did you underclock it though?

    I've had my 8800GTS at this config for the past 6 months now, no problems so far.
  21. epsilon84 said:
    How far did you underclock it though?

    I've had my 8800GTS at this config for the past 6 months now, no problems so far.


    As far as RivaTuner could go:



    Normal (Evga 8800GTS 320MB KO) at 588mhz



    Turned down at 294mhz... :lol:

    Now you have to remember these readings were before I put my new TV card in... so just adding that card, was 7watts, and thats not even watching tv. And one weird thing I noticed, when I close the TV program, the consumption stays the same like I didn't even turn the tv card off.. I have to switch it to composite, then the consumption goes back to the... err.. normal 170Watts.
  22. Gaming rig no. File server yes.
  23. not really. it is all fine by me.
  24. Grimmy said:
    As far as RivaTuner could go:

    http://members.cox.net/fade.2.black/temp/8800-p3-nor.jpg

    Normal (Evga 8800GTS 320MB KO) at 588mhz

    http://members.cox.net/fade.2.black/temp/8800-p3-red.jpg

    Turned down at 294mhz... :lol:

    Now you have to remember these readings were before I put my new TV card in... so just adding that card, was 7watts, and thats not even watching tv. And one weird thing I noticed, when I close the TV program, the consumption stays the same like I didn't even turn the tv card off.. I have to switch it to composite, then the consumption goes back to the... err.. normal 170Watts.


    Use ATITool, I got my 8800GTS 320M down to 85MHz (and it still runs ut2004 at 60fps!)
  25. yes to me. I get an awfull electrical energy bill. but everything I use is electric, even the ovens and heaters.
  26. For me, it depends on the machine.

    For my NAS box, yes, heat and power consumption are a factor because my NAS runs 24/7/365.

    It's also a factor with my HTPC as a lower watt proc produces less heat and can be made to run quieter as to not have to hear fan noise in my living room.

    However, for my main workstation/gaming machine, heat, power consumption, and noise be damned! I want the best performing proc I can afford regardless. Besides, I like keeping Scythe and Zalman in business.
  27. I do equate Power Consumption with Heat which I equate to Noise.

    Also, if you are the actual person paying the power bills, a significant difference in power consumption could be a "noticible" figure over time.

    If you are considering "price" when buying a CPU, then power consumption is also important. If you start tossing around $20 here or $20 there arguments, its quite important. Especially if comparing two different systems.

    For the home user it's not a big deal, but as you said maybe more for companies. But then again, companies may not care either. It all depends on who is paying the bill. While in a "perfect" world, the IT department might care about electrical bills, if it's not in their budget they will not.
  28. No power consumption is usually not a factor for most of my builds (unless they are SFF PCs, severs, 24/7 PCs). I usually worry more about PSU quality, amps (on the +12, etc), and Watts.
  29. Yes, mainly because of heat and as a comparison factor when building PCs for other. It may also allow me to save some bucks with getting a less powerful CPU.

    More so when choosing GPUs though. For instance, the 2900Pro compared to the 8800GTS... I chose the GTS mainly because of less power consumption with less heat in turn.

    For my personal gaming PC... I overclock anyway... so it wouldn't matter
  30. Well if that were the case for me I would not have bought the 125v 6000 AMD Dual Core. I could care less what voltage its sucking up as long as the chip preforms at the rate stating by AMD. I do not overclock for the simple reason WHY???? If you want it to go faster buy the bigger chip.
  31. ^WHY buy a faster chip, when you can OC a cheaper one for same or better performance for the cost of a few months off the CPU life. By the time the CPU dies you would have moved by a several generations. See my sig. (the Celeron D). its been running WAY above rated clock and still alive and kicking.
  32. overclocking is a madness :lol: :pt1cable:
    also, it would only die if you overvolt.
    I couldn't get my X2 EE nor even close to 2.5 stable without raising the voltage.
    And well, I can't overclock too much with my asrock board, it lacks more voltage options. But I reached 2.6 stable on the earlier Athlon 939 I had on this same asrock board.
  33. I take power consumption into consideration, but performance and noise are also factors.

    I overclock my E6600 to 3.0GHz @ stock voltage, and I cool it with a Scythe Ninja Plus which is pretty quiet. I enable SpeedStep so that the CPU will slow down when not stressed.

    I use ATI Tool to underclock my Radeon X1900XT 512MB down to 200MHz for the core, and 250MHz for the memory. I also reduce the voltages as well, but I don't remember what I set it to. This means when I am just surfing or doing other general stuff, the GPU fan will be virtually silent. When a game is launched ATI Tool brings everything back up to stock speed.

    My Seasonic S12 500 has been tested to be up to 84% power efficient; 78% efficient at the low end. Therefore less electricity is wasted as heat which means the case is not as hot. This will be replace by a Seasonic S12II 550 that is rated up to 88% power efficient. The S12 500 will go into my next HTPC. Oh yeah, dead silent too.
  34. CPU power consumption Psh, a 130W CPU pales in comparison to some of those graphics cards... SLi...
  35. i agree loser777 if you really are buying for a gaming rig **** the proc its not the one using that power its the gpu(s) esp with the oc'd monsters of today just one nvidia 8800 ultra (which is what i have) uses what maybe 200 watts by itself bot to mention if you use SLI or for ati crossfire
  36. The only time I would look at that is if I'm trying to build something HTPC styled where I want to have it have low power and heat draw so I could lower noise. I want to build myself an HTPC, but can't afford one at the moment, so at the moment I don't really think about power consumption, especially not on a gaming/overclocking PC.
  37. <is looking at a AMD BE-2400 for his next build.
  38. UncleDave said:
    Is power consumption even a factor. I think most people will choose a CPU based on a combination of OC & price?


    For a desktop/workstation CPU, my criteria for deciding to go with a specific processor is as follows:

    1. CPU type: single-socket, dual-socket.
    2. Price
    3. Number of cores/threads it can handle.
    4. Performance
    5. Thermal dissipation/power consumption- both idle and varying degrees of load.
    6. Motherboard compatibility

    Nothing else matters much as I don't really care much about the brand or if it will overclock or not. What I do either uses very little CPU power or uses a lot of cores to go fast rather than more clock speed, so more cores > higher clock speed or OCing. Also, my desktop/workstation has to be 24/7 stable under extended period of loading and be able to handle that for the years I keep a system. OCing is not generally synonymous with that unless it is mild enough such that it is probably not all that noticeable except by using a stopwatch.

    For a laptop CPU:

    1. Power consumption/thermal dissipation at idle- this is by FAR the most important.
    2. Power consumption/thermal dissipation at anything except idle
    3. Ability to be undervolted to prolong battery life, especially by dropping the idle voltage.
    4. Power consumption of the chipset it's paired to.
    5. Features of the chipset it's paired to.
    6. Price

    The things that matter to me in a laptop are battery life and noise. I want a quiet laptop that runs for a long time on a single charge. The chipset features have a reasonably large bearing on the usability of a laptop as everything is integrated into the chipset in the kind of laptop I'd look at, and certain chipsets deliver more usable-to-me features than others. And of course, price has somewhat of a bearing as well as I am not made out of money. Performance does not matter one iota as I almost never run my laptop on anything but locked to the idle speed (800 MHz.) That is more than sufficient for my needs as it takes very, very little CPU power to run a word processor, text editor, e-mail client, or Web browser. I also don't care about the number of cores much as doing office-type stuff and notes are very light on the CPU and is also single-threaded. I actually prefer one core in a laptop as it consumes less power and yields longer battery life than a dual- or quad-core CPU of the same process generation and voltage/speed binning. However, single-core laptop CPUs that are worth a damn are very rare. Dual-core CPUs are so cheap that they have gotten to be very pervasive, so only a few models even offer single-core CPUs. Most of them have Celeron Ms, which are crap as they have SpeedStep disabled and draw more power at idle than dual-core CPUs do, completely defeating their purpose to me. I have seen a couple machines with mobile Semprons in them, and those are fine (25 W TDP compared to 31-35 W TDP for C2Ds and AMD duals) as are the Core 2 Solo ULVs, which I have heard exist but have never seen in any computer.
  39. I typically only get to use my PC for a max of 2 hours per day (I work, am happily married, etc. :)). When I don't use it, I put it in standby mode because I like it mostly off, but enjoy the ability to start it in 10 seconds and "shut down" in 3 (I haven't rebooted in 6 months - I love Windows XP!). Some days I don't use my PC, so it stays in standby.

    What I would be interested to see is the power usage of a PC in standby vs actively doing things. I really don't care how much electricity my PC uses while I'm using it - I want it to run as fast as it can when I'm there.

    Although I'm in Oregon and heat shouldn't be an issue, there are 3 computers in the "computer room", so if they were all on 24/7, it would probably make it somewhat toasty, considering the rest of the house is normally 70 degrees when we are home (55-70 when we're not - yay for programmable thermostats).

    So I guess to answer the poll, no, it's not an issue - just because of my use model. Battery life doesn't matter either to me as I have no personal laptop. But for the many people that do have a laptop, I'm sure it's important. For example - I just got a new battery for my work laptop that holds 75% more juice, allowing me to work on it for 4 hours at full CPU. That's very very nice.
  40. ive never shut down any of my computers... i think ill remap that button
  41. NO !

    I think most people don’t even care what processors are in machines any more. It is just people like us (enthusiasts) who even give a damn what ‘new’ technologies are out there…Most ma and pa’s really don’t care…

    For me… best performance unless we are talking 90w – 300w but this is not the case.
  42. Most people here OC. So they probably wouldn't care about power consumption.
  43. thefumigator said:
    overclocking is a madness :lol: :pt1cable:
    also, it would only die if you overvolt.
    I couldn't get my X2 EE nor even close to 2.5 stable without raising the voltage.
    And well, I can't overclock too much with my asrock board, it lacks more voltage options. But I reached 2.6 stable on the earlier Athlon 939 I had on this same asrock board.


    See my sig. The Celeron D is OCed with a Pin mod + Volt mod just because my motherboard couldn't do it. Its been running fine since 2003. Only upgraded the RAM/PSU since then.
  44. Personally, it depends; if it's going to be running 24 hours a day as a server, then power consumption certainly comes into any decision. If it's going to be running a few hours a day editing video or playing games, then the only real requirement is that the consumption is low enough that the fan noise isn't annoyingly loud... with a mid-range graphics card and a few hard disks in the system that seems to leave around 100W for the CPU.

    Certainly I'd like to see the idle consumption of CPUs and GPUs go down, since most PCs spend a lot of time idling while people are web-browsing, word-processing or whatever.
  45. Personnaly no.

    Here in Quebec, the power bill isn't really high and I can easyly live with the extra heat it could produce.

    In the winter, less heating from standard heating device. In the summer well just open teh window...
  46. I've got 2 PC's (A64's 3700+) + 2 19 CRT monitors in 1 small room. It gets crazy hot in here. Yes I do consider power consumption. The lower the power consumption, the less heat. I'm not a gamer and neither is my wife. We work and produce stuff on the PC. We'd rather not sweat to death.
  47. At home, no. At work, yes.
  48. How much power does a midrange gaming desktop consume?
  49. Most quad chips are around 125w....no idea how that translates into cash. Would be interesting to know though...say on an average usage of 6 hours per day?

    For me performance > power usage.
    Sure the heat is tied into usage which affects performance but thats not something i'd factor in when choosing a chip.
    General decision making process goes along the lines of "whats my budget and whats the highest clocks / cores i can get with that budget"

    For big business, its a major issue. Many times ive spoken to an IT head of dept and flogged what it is i flog on the basis of it being greener, which enhances company image and saves on costs in a major way.
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