Guru3D.com Forums

Go Back   Guru3D.com Forums > Hardware > General Hardware
General Hardware Want to talk about anything Hardware related? This is the place, you can discuss it here.


Reply
 
Thread Tools Display Modes
PSU wattage and energy bills
Old
  (#1)
Pzykotik
Maha Guru
 
Pzykotik's Avatar
 
Videocard: GTX 780 "Ghz Edition"
Processor: Intel i7-4770K @ 4.3Ghz
Mainboard: MSI Z87-GD65 GAMING
Memory: 8GB Corsair Vengeance Pro
Soundcard: X-Fi Titanium Fatal1ty
PSU: Revolution 1250W
Default PSU wattage and energy bills - 05-07-2014, 14:47 | posts: 2,544 | Location: Bournemouth

This is going to sound stupid, but what are the energy implications of "bigger" power supplies?

It figures that the bigger a power supply is the more energy it will pull from the mains... But is that necessarily true? I mean, I know there are differences in the efficiency etc of supplies and it makes sense that if the components in a PC only draw X amount of power, then the PSU will only use X amount... Otherwise, what happens with the excess energy...

Can anybody make sense of things for me?
   
Reply With Quote
 
Old
  (#2)
Deathchild
Maha Guru
 
Deathchild's Avatar
 
Videocard: HD7950CFX+Qnix2710
Processor: 3770K@4.8GHz delid
Mainboard: Gigabyte Z77X D3H 1.1
Memory: C Vengeance 8GB 1866
Soundcard: VIA VT2021
PSU: Seasonic Platinum 760W
Default 05-07-2014, 15:06 | posts: 2,161 | Location: Estonia

A psu with 90% efficiency will pull 550w from the wall if the required load is 500.

An 80% psu will pull 700w from the wall if the required load is 500. It's the components that make up the power load, not the psu itself.. it's just there to provide it.

Nothing happens with the excess energy (there is no excess energy), bigger psus are just able to supply more if needed than their counterparts.

Last edited by Deathchild; 05-07-2014 at 15:17.
   
Reply With Quote
Old
  (#3)
Pzykotik
Maha Guru
 
Pzykotik's Avatar
 
Videocard: GTX 780 "Ghz Edition"
Processor: Intel i7-4770K @ 4.3Ghz
Mainboard: MSI Z87-GD65 GAMING
Memory: 8GB Corsair Vengeance Pro
Soundcard: X-Fi Titanium Fatal1ty
PSU: Revolution 1250W
Default 05-07-2014, 15:16 | posts: 2,544 | Location: Bournemouth

Good, that's what I thought. Even if I didn't make much sense when asking the question.

I sometimes wonder how I've forgotten all my high school science classes. Too much tinkering with Windows Server...

Thanks!
   
Reply With Quote
Old
  (#4)
Deathchild
Maha Guru
 
Deathchild's Avatar
 
Videocard: HD7950CFX+Qnix2710
Processor: 3770K@4.8GHz delid
Mainboard: Gigabyte Z77X D3H 1.1
Memory: C Vengeance 8GB 1866
Soundcard: VIA VT2021
PSU: Seasonic Platinum 760W
Default 05-07-2014, 15:19 | posts: 2,161 | Location: Estonia

Yeah no worries.
   
Reply With Quote
 
Old
  (#5)
Pinocchio
Master Guru
 
Pinocchio's Avatar
 
Videocard: msi hawk 5770
Processor: intel i5-750
Mainboard: ga-p55a-ud3r
Memory: corsair 4gb 1600
Soundcard: realtek alc889
PSU: corsair vx 450w
Default 05-07-2014, 19:04 | posts: 161 | Location: sweden

Quote:
Originally Posted by Deathchild View Post
A psu with 90% efficiency will pull 550w from the wall if the required load is 500.

An 80% psu will pull 700w from the wall if the required load is 500. It's the components that make up the power load, not the psu itself.. it's just there to provide it.
Required load is 500w

90% efficiency: 500/0.9 = will pull 555w

80% efficiency: 500/0.8 = will pull 625w

Is my math wrong ?
   
Reply With Quote
Old
  (#6)
Extraordinary
Ancient Guru
 
Extraordinary's Avatar
 
Videocard: EVGA GTX980 SC ACX2.0 4GB
Processor: FX-8350 @ 4.8GHz / H100i
Mainboard: ASUS Crosshair V Formula
Memory: 12GB 2133 G.Skill
Soundcard: 5.1 Surround
PSU: Corsair TX950
Default 05-07-2014, 19:05 | posts: 7,906 | Location: 127.0.0.1

Efficiency aside, a 1000w PSU will pull no extra from the wall than a 500w PSU, if you are only pulling 200w load

That's my understanding of it
   
Reply With Quote
Old
  (#7)
Barry J
Maha Guru
 
Barry J's Avatar
 
Videocard: X2 EVGA 660ti SC SLi 3D
Processor: i5 4690K H100i @4.5 1.3v
Mainboard: Asus Z97 MAXIMUS VII Hero
Memory: 16GB 1600 4x4GB
Soundcard: onboard
PSU: EVGA SuperNOVA 1300w G2
Default 05-07-2014, 20:49 | posts: 1,655 | Location: Ipswich UK

I use at full load about 50% of what my PSU can output but at 50% I get the best efficiency 93% @ 700w from my PSU that's one of the reasons why I went bigger the other was never worrying about what hardware I can use without changing PSU .
It cost me more to buy and it is more than I need, but it costs me less to use.

http://www.techpowerup.com/reviews/E...G2_1300/6.html

Last edited by Barry J; 05-07-2014 at 21:03.
   
Reply With Quote
Old
  (#8)
-Tj-
Ancient Guru
 
-Tj-'s Avatar
 
Videocard: ZOTAC GTX780 OC AmpFan
Processor: i7 4770K OC 4.7GHz @1.28v
Mainboard: ASUS Z87 Deluxe
Memory: Crucial BLE 16GB 2400MHz
Soundcard: Creative X-Fi Titanium HD
PSU: Chieftec NTRO88+ 650W
Default 05-07-2014, 21:04 | posts: 8,497 | Location: Urban`Jungle

Will you get that RPGgamesplayer deal?,

Imo that would save you more money, i7 920 OC'ed consumes at least 1x more power then highly Oc'ed 4770K

+ extra perf. up to 100% for sure, I mean I saw min 150%-200% vs my old Oc'ed q9450@ 3.6ghz.
   
Reply With Quote
Old
  (#9)
Pzykotik
Maha Guru
 
Pzykotik's Avatar
 
Videocard: GTX 780 "Ghz Edition"
Processor: Intel i7-4770K @ 4.3Ghz
Mainboard: MSI Z87-GD65 GAMING
Memory: 8GB Corsair Vengeance Pro
Soundcard: X-Fi Titanium Fatal1ty
PSU: Revolution 1250W
Default 05-08-2014, 08:48 | posts: 2,544 | Location: Bournemouth

I was really lucky (who knew being online so often would pay off), and I did get the deal.

The machine feels VERY quick after build. The move to Windows 8 helps quite a bit I think, and knowing that it'll save me money is great news! I got a new PSU from Jonny Manc as well, and didn't know if it was worth me changing down to it (1250W to 750W).
   
Reply With Quote
Old
  (#10)
-Tj-
Ancient Guru
 
-Tj-'s Avatar
 
Videocard: ZOTAC GTX780 OC AmpFan
Processor: i7 4770K OC 4.7GHz @1.28v
Mainboard: ASUS Z87 Deluxe
Memory: Crucial BLE 16GB 2400MHz
Soundcard: Creative X-Fi Titanium HD
PSU: Chieftec NTRO88+ 650W
Smile 05-08-2014, 13:37 | posts: 8,497 | Location: Urban`Jungle

Yeah nice, have fun
   
Reply With Quote
 
Old
  (#11)
scoter man1
Ancient Guru
 
scoter man1's Avatar
 
Videocard: Evga GTX 570/Korean 1440p
Processor: Intel Core i7 4790K
Mainboard: Asus Sabertooth Z97 Mark1
Memory: GSkill Trident X 2x4GB
Soundcard: Onboard/Superlux HD660
PSU: XIGMATEK 750w
Default 05-08-2014, 18:56 | posts: 4,301 | Location: MI, USA

Quote:
Originally Posted by Extraordinary View Post
Efficiency aside, a 1000w PSU will pull no extra from the wall than a 500w PSU, if you are only pulling 200w load

That's my understanding of it
I think that's only relatively true. I think I remember seeing a curve from a psu where at certain usage percentages, it's more efficient than others.

For example <10% was like 82% efficient
between 10 and 90 was 87% efficient
and above 90% was lower again.

The bronze/silver/gold/platinum rating is given to whatever is the lowest efficiency, I think.
   
Reply With Quote
Old
  (#12)
Extraordinary
Ancient Guru
 
Extraordinary's Avatar
 
Videocard: EVGA GTX980 SC ACX2.0 4GB
Processor: FX-8350 @ 4.8GHz / H100i
Mainboard: ASUS Crosshair V Formula
Memory: 12GB 2133 G.Skill
Soundcard: 5.1 Surround
PSU: Corsair TX950
Default 05-08-2014, 19:03 | posts: 7,906 | Location: 127.0.0.1

Quote:
Originally Posted by scoter man1 View Post
I think that's only relatively true. I think I remember seeing a curve from a psu where at certain usage percentages, it's more efficient than others.

For example <10% was like 82% efficient
between 10 and 90 was 87% efficient
and above 90% was lower again.

The bronze/silver/gold/platinum rating is given to whatever is the lowest efficiency, I think.
Yea that makes sense, I was trying to put into words that a 1000w PSU doesn't necessarily mean it will cost more than a 500w PSU to run if your system only uses 200w

The 1000w gold efficiency rated PSU could be cheaper to run than the 500w non-efficient PSU
   
Reply With Quote
Old
  (#13)
k3vst3r
Ancient Guru
 
k3vst3r's Avatar
 
Videocard: Tri-fire 290x Qnix 120Hz
Processor: i7 4770k 4.6
Mainboard: Asus Maximus Hero VI
Memory: 4x4GB 2400
Soundcard: SB X-FI Titanium
PSU: Corsair AX1200i
Default 05-08-2014, 19:06 | posts: 3,076 | Location: Sheffield UK

tends to be above 20% to 100%

below this an might be little more inefficient


   
Reply With Quote
Old
  (#14)
Pzykotik
Maha Guru
 
Pzykotik's Avatar
 
Videocard: GTX 780 "Ghz Edition"
Processor: Intel i7-4770K @ 4.3Ghz
Mainboard: MSI Z87-GD65 GAMING
Memory: 8GB Corsair Vengeance Pro
Soundcard: X-Fi Titanium Fatal1ty
PSU: Revolution 1250W
Default 05-09-2014, 12:47 | posts: 2,544 | Location: Bournemouth

Totally.




My CPU is most efficient around the 50% mark (91%), dropping to 88% at highest power draw.
   
Reply With Quote
Old
  (#15)
Anarion
Ancient Guru
 
Anarion's Avatar
 
Videocard: Gigabyte GeForce GTX 970
Processor: Intel Core i7 3770K
Mainboard: ASUS P8Z77-V
Memory: G.SKILL RipjawsX 16 GB
Soundcard: Sound Blaster Zx + HD 595
PSU: Corsair AX760
Default 05-09-2014, 13:04 | posts: 11,152 | Location: Finland

You are barely hitting that 20% with your rig.
   
Reply With Quote
Old
  (#16)
Pzykotik
Maha Guru
 
Pzykotik's Avatar
 
Videocard: GTX 780 "Ghz Edition"
Processor: Intel i7-4770K @ 4.3Ghz
Mainboard: MSI Z87-GD65 GAMING
Memory: 8GB Corsair Vengeance Pro
Soundcard: X-Fi Titanium Fatal1ty
PSU: Revolution 1250W
Default 05-09-2014, 13:46 | posts: 2,544 | Location: Bournemouth

Quote:
Originally Posted by Anarion View Post
You are barely hitting that 20% with your rig.
Eh? 20% is 250W... I recon I'm using about 500...
   
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump



Powered by vBulletin®
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
vBulletin Skin developed by: vBStyles.com
Copyright (c) 1995-2014, All Rights Reserved. The Guru of 3D, the Hardware Guru, and 3D Guru are trademarks owned by Hilbert Hagedoorn.