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Electric Bill

For just the CPU, you go from 130w TDP to 95w TDP theoretically saving you 35w at full load. Not sure about the idle watts though
 
Is this thread for real?

Yeah. I mostly use rig 1... my other is just to game with and only on when gaming. This machine is on sometimes maybe 8hrs at a time. Usually on after work till the end of the day round 11pm.. from say 4pm so it sees about 6-7hrs a day, during the week.. so I'm looking to maybe cut down on the electric bill while keeping my computer habits the same. I've put all my backup drives on a HDD power switch. Lian Li HDD power switch.

I know running a lower wattage PSU can save on idle watts. I've only seen it once when I installed a Seasonic 400w Gold on my old rig I gave to my brother. That was after being powered by a 950w Silver rated PSU. But I'm not 100% sure it was just the PSU that did this. I know a few less fans were used... i think they took 7-8w per fan.. So I'm sorta thinking that going with a Z68 with no GPU... Make sense?
 
How much power/watts would I save goin from Rig 1 to an i5 2500 or 2600, K platform?

From what i've seen the difference isn't huge in terms of total system power draw - 10W max. The 2600 will likely have higher temps, so you may need slightly beefier cooling for it if you want to overclock, though.
 
How much power/watts would I save goin from Rig 1 to an i5 2500 or 2600, K platform?

Not much, you might be looking at saving $5/month at the absolute tops.

I would recommend waiting for Ivy Bridge if your goal is to reduce power-consumption while maintaining i7-920 level performance. The nehalem -> SB delta just isn't large enough to justify the capital outlay to acquire the SB system.
 
Not much, you might be looking at saving $5/month at the absolute tops.

I would recommend waiting for Ivy Bridge if your goal is to reduce power-consumption while maintaining i7-920 level performance. The nehalem -> SB delta just isn't large enough to justify the capital outlay to acquire the SB system.

Thanks big-man 🙂
 
Not much, you might be looking at saving $5/month at the absolute tops.

I would recommend waiting for Ivy Bridge if your goal is to reduce power-consumption while maintaining i7-920 level performance. The nehalem -> SB delta just isn't large enough to justify the capital outlay to acquire the SB system.

Hey, that's 60 bucks over the course of a year. $5 here and $5 there, eventually you're making some nice savings.
 
If you're running stock, could you fiddle with lowering GPU or CPU voltages? For me that was good for at least idle 5 degrees and 10 load which should correspond to some power difference.
 
Hey, that's 60 bucks over the course of a year. $5 here and $5 there, eventually you're making some nice savings.
he said 5 bucks tops. it could easily be only 2 or 3 bucks a month. if that kind of savings is important then you have bigger problems.
 
My Q9300 rigs idle at around 98 watts. Since I couldn't afford yet to change them out for G530 / Z68 rigs, I decided to set them to sleep after 30 minutes.

Yet my electric bill went up, not down. I blame the AC.
 
Yeah. I mostly use rig 1... my other is just to game with and only on when gaming. This machine is on sometimes maybe 8hrs at a time. Usually on after work till the end of the day round 11pm.. from say 4pm so it sees about 6-7hrs a day, during the week.. so I'm looking to maybe cut down on the electric bill while keeping my computer habits the same. So I'm sorta thinking that going with a Z68 with no GPU... Make sense?

No it doesn't really make any sense since a Z68 mobo + 2500k CPU is going to run you at least $250 (assuming you buy it at MC). It's going to take 14 years for you to break even with this investment in wattage over an idle i7 920 (with speedstep enabled and all power saving technologies enabled).

If you are really that strapped for cash, sell the i7 920, HD5770, Seasonic 650, Vertex, etc. and just get the cheapest Llano or even Bobcat setup with a $30 Corsair PSU.

he said 5 bucks tops. it could easily be only 2 or 3 bucks a month. if that kind of savings is important then you have bigger problems.

Sometimes people miss the BIG picture. People can save way more $ a month by air drying their clothes on a rack, drinking tap water vs. bottled water, walking/riding their bike to a store 10 min away instead of driving, eating less (shocker!).

Hey, that's 60 bucks over the course of a year. $5 here and $5 there, eventually you're making some nice savings.

It's not going to be $5. You are talking 8 hours a day of idle usage since OP said he uses his other system for games.

2500k vs. i7 (76 vs. 117 watts)

8 hours a day x 365 days x 41 watts x $0.15 c/kW = $17.96 per year or $1.50 / month!!

The OP could sell his HD5770 for $60 and get a GT210 for $15. That's equivalent to 30 months savings in electricity costs between an i7 920 and 2500k in idle speeds....

Yeah. I mostly use rig 1... my other is just to game with and only on when gaming.

The best way in this case to save $ on electricity is to sell the entire system and just use the 2ndary rig for everything! Why do you have 2 separate desktops where you use 1 for games and the other for casual work unless they are shared between 2+ people?
 
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Hey, that's 60 bucks over the course of a year. $5 here and $5 there, eventually you're making some nice savings.

Do a NPV vs. NFV analysis on your TCO and let me know how "nice" those savings look after the 2-3 yr typical lifespan of a rig.

As ghastly as the power-consumption was for my Q6600's, I did not replace them with i7-920's.

There are definite cases where replacement for the sake of reducing power-consumption can and does work in your favor from an economic standpoint, but traditionally you need to be making a two-node jump (65nm -> 32nm, 45nm -> 22nm) in order for the economics to really work in your favor once you've accounted for the capital outlays involved in acquiring the newer equipment.
 
Not worth it from both a performance and power standpoint.

Performance - ~10% faster clock for clock
Power - 50W x $0.08/kW-hr x 24 x 365 = $35

Also factor in the time to install the new hardware and/or OS (updating, reimaging, etc.)
 
If you are really that strapped for cash, sell the i7 920, HD5770, Seasonic 650, Vertex, etc. and just get the cheapest Llano or even Bobcat setup with a $30 Corsair PSU.


this.

ive contemplated retiring this rig to exclusively gaming use and building a zacate system until one of my friends say they want to play some game. thats when i would fire up the gaming rig.
 
Thanks for doing some Math on this.

No it doesn't really make any sense since a Z68 mobo + 2500k CPU is going to run you at least $250 (assuming you buy it at MC). It's going to take 14 years for you to break even with this investment in wattage over an idle i7 920 (with speedstep enabled and all power saving technologies enabled).

I would try n get, in selling the i7 920 platform, what it would cost for the MB (Z68), Ram, and CPU, and yes I have a MC nearby. And if I did this the savings, if any, would immediately begin. But yes I understand it's not alot.



If you are really that strapped for cash, sell the i7 920, HD5770, Seasonic 650, Vertex, etc. and just get the cheapest Llano or even Bobcat setup with a $30 Corsair PSU.

I still do some AVCHD video stuff so I sort of need the horses. I've thought about it though.



It's not going to be $5. You are talking 8 hours a day of idle usage since OP said he uses his other system for games.

2500k vs. i7 (76 vs. 117 watts)

8 hours a day x 365 days x 41 watts x $0.15 c/kW = $17.96 per year or $1.50 / month!!

The OP could sell his HD5770 for $60 and get a GT210 for $15. That's equivalent to 30 months savings in electricity costs between an i7 920 and 2500k in idle speeds....

For some personal reason I feel this i7 920 is a power hog even though the math says otherwise. Maybe because of the 130w TDP... it's some weird delusion i have :hmm: 😕

The best way in this case to save $ on electricity is to sell the entire system and just use the 2ndary rig for everything! Why do you have 2 separate desktops where you use 1 for games and the other for casual work unless they are shared between 2+ people?

The gaming rig idles way higher cause of the overclocking and I think the GPU too. And after my first P4 423 socket machine I always had 2 rigs.
 
Not sure what that means. I understand that some people may not care about 5$ a month. However, I do so I thought it was worth mentioning. Looks like that was in error.

Even for those who do care about $5, you aren't saving anything if you have to invest $300 in hardware expenditures just to have the opportunity to save $60 per year in eletrical costs.

In a net-present-value (NPV) analysis you are looking at 5 yrs minimum to come out in that deal assuming the $300 you need to spend on computer parts would have earned 0% ROR were it invested in something else for those five years.

Its not fancy math or fast-and-loose wallstreet style investment advice, its just a simple cost-reward analyses. You don't save any money by spending more money than you are/were ever going to save.
 
Hey, that's 60 bucks over the course of a year. $5 here and $5 there, eventually you're making some nice savings.

Seriously, I'd invest in some books and pave a better solution than worry about a PC's electrical use.

I am doing just that in my life now, should have been doing it sooner. More than doubled my salary in 8 years, plan to double it again in another 4. I started the journey a bit on a the higher side in five figures.
 
How much power/watts would I save goin from Rig 1 to an i5 2500 or 2600, K platform?

not enough for global domination on the power market.... 😀

in all honesty.... you'd probably save more power charging your cell phone from a solar charger every day, then u downgrading...
 
The gaming rig idles way higher cause of the overclocking and I think the GPU too. And after my first P4 423 socket machine I always had 2 rigs.

You already are contemplating selling the i7 920, right? Sell the entire system and see if you can live with only 1 desktop. If not, you can always buy the more efficient 22nm IVB in the spring of next year. A lot of the components you have in that system are very high end for an "idle" system. $130 X650 Seasonic PSU?

$29 Corsair 500W with $10 off. My point is, you can probably sell your entire system and get more power efficient components without losing much performance. What do you need an HD5770 in that system for? If you get rid of 920+mobo+ram+5770+seasonic, you can just grab a i5-2400 and Z68/H67 mobo for $80 and use SB GPU.

Don't worry about TDP so much since your main system isn't really loaded.

Even among modern processors with TDPs ranging from 35W (i5-2390), 45W (i5-2500T) to 95W (i5-2500), there is not much there at idle. TDP is useless for measuring Idle power consumption efficiency because most processors idle around 1.6 with EIST:

table3.png


You can see that even 35-45W TDP CPUs only manage to save you 1-2W of power at idle.

power-5.png

power-1.png


Load CPU-Z and see what frequency your i7 920 idles at. If C1-C3, C6 and EIST are enabled, your CPU should also drop to 1.6ghz.

"All CPUs from this series drop their frequency to 1.6GHz in idle mode that is why we see identical power consumption readings" ~ Xbitlabs
 
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I am/was in a similar boat (I think you commented on my thread actually). I had a Q9650 @4Ghz with a bunch of HDDs pulling 150w+ at idle that I just took apart. I'm in the process of putting together the new version with a 2600k and yanking out some RAID0's and replacing with SSDs, and "probably" not going to overclock (or at least not yet anyway). I'm hoping idle consumption comes down to under 100w.

What people sometimes tend to overlook in the power consumption issue is heat. I know my A/C bill went up whenever I had to leave my main rig on for long periods of time. And it also has the reverse impact in the winter. If the computer(s) are in a tiny room such as a bedroom or office that compounds the issue. Granted its not a ton of money, and if you use a budget plan with your power company it has less of an impact. The net over the course of a year may vary depending on your area, as some energy bills are higher/lower as the seasons change.

By itself, just changing your CPU/mobo/GPU won't make too much of a difference, but if you couple it with some other energy saving techniques (see the solar phone charging idea above) and maybe a change in habits AND as long as the upgrade itself doesn't cost you a ton (net, by selling old gear), then it is worth it.
 
You're potentially saving right around 30 watts at idle, which will usually be very close to your average power savings.

So take 1000 and divide it by your power saved and you get 33.

For every 33 hrs of run time you are saving 1kwhr, which typically costs about 10 cents. If you run 33 hrs a week you save a dime. Woohoo. 66 hrs a week you save 2 dimes a week, or 8 dimes a month. Obviously its not worth it unless all you got is dimes, and the 2500k is free.
 
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