Actual Wattage Required by High End Systems

ArchAngel777

Diamond Member
Dec 24, 2000
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I picked up a pretty nice APC Battery Backup. 1300VA (780 Watts) and hooked up my computer to it. I was curious, what was the draw with my computer, monitor and peripherals plugged in? Not much...

180 Watts idle within Windows Vista

265 Watts Load P95 (4 cores)

285 Watts Lost Planet (Utilizes 4 Cores + Hammers my 8800GTS)

My system is

Q6600 @ 3.33Ghz 1.35v (B3)
ThermalRight SI-128 SE + Silverstone 120MM fan (110CFM)
Abit IP35-E
4x1GB Trascend 4-4-4-12
8800GTS 640MB OC2 @ 620/2000
74 GB Raptor
500 GB USB External 'My Book'
Samsung DVD-Burner
SB Audigy
4 120MM Case Fans
Cable Modem
Wireless Router
Samsung 21.6" LCD (216BW)
Antec TPQ 850 WATT (Up to 88+% effeciency)

I expected my power draw would be far greater than it really is... But, I guess I was wrong.

Just thought I would let everyone know that some of the power requirements stated might be overkill and certainly are in my situation. Numbers would climb 20 watts if I moved to a GTX, maybe 30 watts if I moved to an Ultra.
 

SparkyJJO

Lifer
May 16, 2002
13,357
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81
Also a note, that is AC watts, so taking the PSU efficiency into consideration we are looking at about 228 watts at 80% efficiency.

Now also something to bear in mind is don't get a 250W PSU for that, because you have to consider that the lower wattage PSUs probably won't have enough on the 12V lines, and PSUs don't like being stressed at their max capacity very much (also their efficiency suffers). Around 2/3 to 3/4 of total load is most PSU's sweet spot, so take the consideration of the 12V amperage and then the operation range of the PSU and you are looking at a 350-400W unit. That's it. Of course make sure it isn't some crappy piece of junk (like okia or raidmax or something!). As PSUs age they do lose capacity gradually (well-built ones don't nearly as fast) so for that system for long-term usage, 450W would be just about right.

Now the thing is some people buy a PSU and don't expect to upgrade it as they upgrade the PC the next few generations of gfx cards and such, so sometimes getting a little overkill now may help in the future a year or two. I have a 620W Corsair and I know I shouldn't have to replace it for a long time.
 

ArchAngel777

Diamond Member
Dec 24, 2000
5,223
61
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Originally posted by: SparkyJJO
Also a note, that is AC watts, so taking the PSU efficiency into consideration we are looking at about 228 watts at 80% efficiency.

Now also something to bear in mind is don't get a 250W PSU for that, because you have to consider that the lower wattage PSUs probably won't have enough on the 12V lines, and PSUs don't like being stressed at their max capacity very much (also their efficiency suffers). Around 2/3 to 3/4 of total load is most PSU's sweet spot, so take the consideration of the 12V amperage and then the operation range of the PSU and you are looking at a 350-400W unit. That's it. Of course make sure it isn't some crappy piece of junk (like okia or raidmax or something!). As PSUs age they do lose capacity gradually (well-built ones don't nearly as fast) so for that system for long-term usage, 450W would be just about right.

Now the thing is some people buy a PSU and don't expect to upgrade it as they upgrade the PC the next few generations of gfx cards and such, so sometimes getting a little overkill now may help in the future a year or two. I have a 620W Corsair and I know I shouldn't have to replace it for a long time.

I totally agree... I just think before telling someone they need a 1000W PSU, people should see for themselves that that kind of power is not needed.

Better to go OVER than UNDER. But no need to spend $300 on the lastest 1000W PSU. Even SLI + Q6600 + 5 HDD will not pull more than ~450 watts under load. So, at 65% PSU efficienty (crappy PSU) you are looking at needing a junky 650 WATT or a Quality 550 WATT in that worst case scenario... Of course, then there is no room for growth, but still... Even the next round of GPU's are not likely to pull more than another 25% more power over the current ones. Heck, they may even require less power due to the die shrink.

Although I am very happy with my PSU purchase, I feel it was overkill. However, it is 80 plus certified and I picked it up for $159... No regrets, but I can see right now that I am barely putting any load on this PSU and will last me longer than the warranty... Then when it fails, have to buy a new one anyway...
 

jonmcc33

Banned
Feb 24, 2002
1,504
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This is very true and I wish that more people realized this before wasting money on 1kW PSUs or the dual PSU solution. Just crazy...
 

Modelworks

Lifer
Feb 22, 2007
16,240
7
76
my system with a 7900gtx, 3ghz cpu averages 185 watts according to the ups.
People tend to go crazy with power supplies.
 

JEDIYoda

Lifer
Jul 13, 2005
33,981
3,318
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Originally posted by: jonmcc33
This is very true and I wish that more people realized this before wasting money on 1kW PSUs or the dual PSU solution. Just crazy...

dude...most people know they don`t need a 1k or even an 850watt PSU!!


sad to say it`s called e-penis...as in whose is bigger......

People are not as nieve as you people think they are.

But hell why not get a 1k or even an 850 watt if mommy and daddy are forking over the money for your new rigg??

As has been pointed out elsewhere......
Most people buy bigger so they won`t have to buy a new PSU everytime they upgrade.

Also to those of you who see people wasting there money (as you would call it) purchasing a 1k PSU`s...
There arre several things to consider and the first one is that it is there money not yours.
Second one is most 250 watt PSU`s don`t have the jiuce on the 12v rail to run things.

Also I have never seen a PSU company decie that little is enough....the main reason there are obly a handful of you who believe little is enough thus they cannot possibly make any money reinventing the 200watt PSU!!

To the OP......there is noway your APC can even figure into the equation...
OP`s statement from another thread-- Well, the way the APC works is that the power charges the battery while the battery feeds the power to the PC. It reports the watts drained from the battery at any given time on the LCD display that it has. So if the unit had to supply more than it's rating (780 Watts) then the unit would blow the built-in circuit breaker.

In any event, I am not sure why you would suggest that the wattage drain on my UPS would be incorrect.

So, if you have something to say, tell me... Because as I understand it, I am not sure how it could be wrong.


Edit ** And I already read through Johny Guru's thread that you posted. He didn't state all power supplys cause this 'issue' and implied it was a minority of PSUs. At least that is what I gathered from his multiple posts within that thread. He also said that there is a way to accurately measure AC consumption, just not something he has access to, or something he even knows about.

I suppose the way to test it wuld be to figure out how many Watt hours my battery backup is rated for and unplug it from the wall at idle and see how long the PC lasts then average it out.


Note even the Op is grasping for straws...


Then Jonny shows that killAWatt can be diecieving--
MYTHBUSTERS!

Why did I measure DC instead of measuring the AC and calaculating for efficiency? Because your Kill-A-Watt, Power Angel, or whatever tells you you're only pulling 150W from the wall may actually be WAY OFF. I would like to direct your attention to these videos:
http://www.jonnyguru.net/forum...hp?p=29345&postcount=8
and

http://www.jonnyguru.net/forum...p?p=29409&postcount=15

I believe the problem is with the APFC circuit. Somehow the harmonics correction throws whatever these devices use to measure current. Can't say for sure. But whenever someone says "I only measured 200W AC power consumption from the wall so I only need a 300W for a pair of 8800GTS cards," I'm going to say, "Find a way to measure the DC output instead and get back with me because I'm not buying your numbers." Sorry. FYI: I used multiple data-logging clamping ammeters on every output of the PSU to get my numbers. Then added up the results of all of the meters.






 

jonmcc33

Banned
Feb 24, 2002
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Originally posted by: JEDIYoda
dude...most people know they don`t need a 1k or even an 850watt PSU!!

I don't think they do because I always see someone asking how powerful of a PSU they need with a listing of their specs and someone always says something stupid like 750W or more. I see it all over forums on the web.

So you have lots of people that don't know what they need and lots of people giving them wrong advice. That's "most" people knowing that they don't need a 1kW PSU? Not at all sad to say.
 

ArchAngel777

Diamond Member
Dec 24, 2000
5,223
61
91
Originally posted by: JEDIYoda
words


Jedi,

You never responded to my post in that thread... If you are going to masquerade around, why not just go in there and refute what I wrote? Prove to me that an APC is unable to display the actual wattage leaving the unit from the AC without taking Johny's word for it. I can call into question his numbers just as easy as he can do it to someone else... So, go ahead and refute it with technical prowess that you obviously do not possess. Your ad hominem attack is pathetic.

Argue the facts, not the person... You can tell me I am grasping for straws, but if you don't address where I am wrong and explain WHY, then you have nothing at all.

Edit ** And the links in your posts are broken... Do you not know how to link properly?
 

JEDIYoda

Lifer
Jul 13, 2005
33,981
3,318
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Originally posted by: ArchAngel777
Originally posted by: JEDIYoda
words


Jedi,

You never responded to my post in that thread... If you are going to masquerade around, why not just go in there and refute what I wrote? Prove to me that an APC is unable to display the actual wattage leaving the unit from the AC without taking Johny's word for it. I can call into question his numbers just as easy as he can do it to someone else... So, go ahead and refute it with technical prowess that you obviously do not possess. Your ad hominem attack is pathetic.

Argue the facts, not the person... You can tell me I am grasping for straws, but if you don't address where I am wrong and explain WHY, then you have nothing at all.

Edit ** And the links in your posts are broken... Do you not know how to link properly?

So let me get thi right your backing up your position with technical prowess....stranger things have happenned...

links work fine for me...hmmmm
 

ArchAngel777

Diamond Member
Dec 24, 2000
5,223
61
91
Originally posted by: JEDIYoda
Originally posted by: ArchAngel777
Originally posted by: JEDIYoda
words


Jedi,

You never responded to my post in that thread... If you are going to masquerade around, why not just go in there and refute what I wrote? Prove to me that an APC is unable to display the actual wattage leaving the unit from the AC without taking Johny's word for it. I can call into question his numbers just as easy as he can do it to someone else... So, go ahead and refute it with technical prowess that you obviously do not possess. Your ad hominem attack is pathetic.

Argue the facts, not the person... You can tell me I am grasping for straws, but if you don't address where I am wrong and explain WHY, then you have nothing at all.

Edit ** And the links in your posts are broken... Do you not know how to link properly?

So let me get thi right your backing up your position with technical prowess....stranger things have happenned...

links work fine for me...hmmmm


LOL, nice, if anyone is smart enough they can look at your edit date within that post and find that it was AFTER my edit date within my post below, thus you edited the links. You are a fraud.
 

aigomorla

CPU, Cases&Cooling Mod PC Gaming Mod Elite Member
Super Moderator
Sep 28, 2005
20,839
3,174
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uhhh...

okey my UPS says 563W on my main rig.

What does she have?

P5K-DLX /w Q6600 G0 @ 1.44Vcore 100% loaded 24/7
8800GTX x 2
4 x Raptors 74gigs on RAID 0
2 x Lightscribe DVD+-RW
Liang D5 pumps
12 x 120mm Yate Loon Fans.


So my 850W antec Quattro maybe overkill. However its one of the most stable PSU's jonnyguru tested.

I dont care about max voltage, i care more about stable power. If you can show me a 600W PSU thats MORE stable then my Antec Quattro, id try it out. Unfortunately the MOST stable PSU's are killer e-penius PSUs.


And yes my antec Quattro will spank a corsiar HX series in stability as well as a seasonic. The only PSU it loses to is the TT's 1kw and 1.2Kw series. :T

 

ArchAngel777

Diamond Member
Dec 24, 2000
5,223
61
91
Originally posted by: aigomorla
uhhh...

okey my UPS says 563W on my main rig.

What does she have?

P5K-DLX /w Q6600 G0 @ 1.44Vcore 100% loaded 24/7
8800GTX x 2
4 x Raptors 74gigs on RAID 0
2 x Lightscribe DVD+-RW
Liang D5 pumps
12 x 120mm Yate Loon Fans.


So my 850W antec Quattro maybe overkill. However its one of the most stable PSU's jonnyguru tested.

I dont care about max voltage, i care more about stable power. If you can show me a 600W PSU thats MORE stable then my Antec Quattro, id try it out. Unfortunately the MOST stable PSU's are killer e-penius PSUs.


And yes my antec Quattro will spank a corsiar HX series in stability as well as a seasonic. The only PSU it loses to is the TT's 1kw and 1.2Kw series. :T

You have an ultra high end computer bro... You represent like .0001% of PC users out there... For YOU that kind of power is needed or advised. But most people do not run SLI, nor do they run an insanely clocked Q6600!

I also really LIKE my Antex TPQ 850.
 

aigomorla

CPU, Cases&Cooling Mod PC Gaming Mod Elite Member
Super Moderator
Sep 28, 2005
20,839
3,174
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Originally posted by: ArchAngel777
Originally posted by: aigomorla
uhhh...

okey my UPS says 563W on my main rig.

What does she have?

P5K-DLX /w Q6600 G0 @ 1.44Vcore 100% loaded 24/7
8800GTX x 2
4 x Raptors 74gigs on RAID 0
2 x Lightscribe DVD+-RW
Liang D5 pumps
12 x 120mm Yate Loon Fans.


So my 850W antec Quattro maybe overkill. However its one of the most stable PSU's jonnyguru tested.

I dont care about max voltage, i care more about stable power. If you can show me a 600W PSU thats MORE stable then my Antec Quattro, id try it out. Unfortunately the MOST stable PSU's are killer e-penius PSUs.


And yes my antec Quattro will spank a corsiar HX series in stability as well as a seasonic. The only PSU it loses to is the TT's 1kw and 1.2Kw series. :T

You have an ultra high end computer bro... You represent like .0001% of PC users out there... For YOU that kind of power is needed or advised. But most people do not run SLI, nor do they run an insanely clocked Q6600!

I also really LIKE my Antex TPQ 850.


:p i dont run sli.

I just have 2 G80GTX powering 2 gateway's 2485W on dual screen setup. When i had my eVGA 680i i did use sli and noticed it didnt give me squat.

Then again, i didnt play anything thta would max out a G80gtx as it is.
 

jonmcc33

Banned
Feb 24, 2002
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Originally posted by: ArchAngel777
LOL, nice, if anyone is smart enough they can look at your edit date within that post and find that it was AFTER my edit date within my post below, thus you edited the links. You are a fraud.

I would have to agree. He didn't even reply to my post after calling me out. If anything the PSU is one of the most misunderstood components of the PC. You have him saying that it isn't. Just odd if you ask me. Very odd.
 

manowar821

Diamond Member
Mar 1, 2007
6,063
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I feel entirely justified in purchasing my DA750.

It's an incredibly stable single 60A rail 100% modular box, and will support SLI and quad cores in the future. $200.00 - Expensive, yeah, but I won't be replacing it for years.
 

SerpentRoyal

Banned
May 20, 2007
3,517
0
0
A high-quality 500 watts PSU will work with ANY single GPU rig. This PSU should also work well with many SLI rigs. Antec Earthwatts 500 costs $30-$50 AR. Unit is warranted for 3 years.
 

JEDIYoda

Lifer
Jul 13, 2005
33,981
3,318
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Originally posted by: manowar821
I feel entirely justified in purchasing my DA750.

It's an incredibly stable single 60A rail 100% modular box, and will support SLI and quad cores in the future. $200.00 - Expensive, yeah, but I won't be replacing it for years.

you are probably correct! Thus if you do upgrade withon the next few years you should not have to purchase a new PSU!!

One less expense for you later!

Peace!!
 

Mucker

Platinum Member
Apr 28, 2001
2,833
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0
Here is my Q6600 system idle: http://members.cox.net/mucker/NoPowersave.jpg

Here is my Q6600 system load: http://members.cox.net/mucker/Loaded.jpg

Both of the above screens are when the VC is idle. With all 4 cores and the VC going full blast, an additional 50W can be added to my loaded value for a total of ~ 420 watts.
See the Xbitlabs calculation between idle and load nVidia 8800 (approx 50 watts): http://www.xbitlabs.com/misc/p...0/8800gts_full.gif&1=1

I picked up a TPQ-850 at buy.com earlier this year for $99. I also picked up a Trio 650 for $50 from buy.com earlier than that. The new Corsair VX for $70 is a complete steal. You don't have to spend a ton to power a high end system......
 

JEDIYoda

Lifer
Jul 13, 2005
33,981
3,318
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Originally posted by: Mucker
Here is my Q6600 system idle: http://members.cox.net/mucker/NoPowersave.jpg

Here is my Q6600 system load: http://members.cox.net/mucker/Loaded.jpg

Both of the above screens are when the VC is idle. With all 4 cores and the VC going full blast, an additional 50W can be added to my loaded value for a total of ~ 420 watts.
See the Xbitlabs calculation between idle and load nVidia 8800 (approx 50 watts): http://www.xbitlabs.com/misc/p...0/8800gts_full.gif&1=1

I picked up a TPQ-850 at buy.com earlier this year for $99. I also picked up a Trio 650 for $50 from buy.com earlier than that. The new Corsair VX for $70 is a complete steal. You don't have to spend a ton to power a high end system......

No but you do need to shop smart and know what you are purchasing!
 

thecoolnessrune

Diamond Member
Jun 8, 2005
9,670
571
126
I have a question but maybe I'm just too unknowledgable in things to know it.. (Never owned a UPS)

But are you talking about 285 AC watts? Like at 120V? If that's the case, then that is only how much power is being pulled at the wall. That still means that after estimation of inefficiencies etc. you're still pulling 450-500 watts off your PSU.

Does it pull much from the wall? No. But don't think that you can get by with a ~300 watt PSU.
 

jonmcc33

Banned
Feb 24, 2002
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Originally posted by: thecoolnessrune
I have a question but maybe I'm just too unknowledgable in things to know it.. (Never owned a UPS)

But are you talking about 285 AC watts? Like at 120V? If that's the case, then that is only how much power is being pulled at the wall. That still means that after estimation of inefficiencies etc. you're still pulling 450-500 watts off your PSU.

Does it pull much from the wall? No. But don't think that you can get by with a ~300 watt PSU.

No, you pull more AC than you do DC. So if it's showing 400W DC being pulled then you're using 320W DC with 80% efficiency.
 

thecoolnessrune

Diamond Member
Jun 8, 2005
9,670
571
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Originally posted by: jonmcc33
Originally posted by: thecoolnessrune
I have a question but maybe I'm just too unknowledgable in things to know it.. (Never owned a UPS)

But are you talking about 285 AC watts? Like at 120V? If that's the case, then that is only how much power is being pulled at the wall. That still means that after estimation of inefficiencies etc. you're still pulling 450-500 watts off your PSU.

Does it pull much from the wall? No. But don't think that you can get by with a ~300 watt PSU.

No, you pull more AC than you do DC. So if it's showing 400W DC being pulled then you're using 320W DC with 80% efficiency.

So what am i missing? We all know that in basic terms Watts equals volts multiplied by amps. So if you're pulling 285 watts AC from the wall, that's about 2.375 amps being pulled from the wall, not including inefficiency. (285=120*2.375). So if you go to a PSU and just to make it simple say its 12V (not including 5V and 3.3V rails). Doesn't that change the equation to how many watts are being produced? Or am I still not getting something..
 

SerpentRoyal

Banned
May 20, 2007
3,517
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If the load is purely resistive, then you can obtain the product of V x A on the input side and V x A on the output side. The output side will show the actual power used by a device. The ratio between ouput and input is efficiency. In the real world, we also have to deal with inductors and capacitors, resulting in real and apparent power. To accurately measure the power used by a PC at any point in time, you will need to obtain the voltage and current flowing thru each DC output wire of the PSU. I have access to a gizmo (weekend G work) that could do the number crunching with the use my custom pig-tails. This gizmo can only handle up to 500 watts.
 

Modelworks

Lifer
Feb 22, 2007
16,240
7
76
Originally posted by: thecoolnessrune


So what am i missing? We all know that in basic terms Watts equals volts multiplied by amps. So if you're pulling 285 watts AC from the wall, that's about 2.375 amps being pulled from the wall, not including inefficiency. (285=120*2.375). So if you go to a PSU and just to make it simple say its 12V (not including 5V and 3.3V rails). Doesn't that change the equation to how many watts are being produced? Or am I still not getting something..

No because the formula volts x amps still applies.
Disregarding efficiency your 285 watts from 120vac would produce 12volts @ 23.75 amps.
google Kirchhoff and maxwell to get more info.
 

Super Nade

Member
Oct 5, 2005
149
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0
Guys, it is not so simple. Kill-A-Watt readings are not always accurate, especially if line distortion and phase displacement factors are not taken into account. It is a lot more complicated than you think. A $30 device won't provide the necessary compensatory services. If you don't know what I'm talking about, don't worry... stay tuned for an article on the pitfalls of basing absolute power requirements on devices like the KillAWatt (will go up on overclockers.com).

I really wish I had one to pull apart and check for myself.....