Sign in with
Sign up | Sign in
Your question
Solved

Choosing The Correct Wattage PSU for my new PC Build

Tags:
  • Power Supplies
  • Hard Drives
  • Wattage
  • Build
  • Corsair
  • SSD
  • Components
Last response: in Components
Share
April 12, 2013 3:17:15 AM

Hi all,

After following these forums for a long time I finally decided to make an account. But I come here asking a question!

What PSU Wattage do you think I would need for this computer build? (Specs Listed Below)

CPU: Intel Core i7 3770k @ 4.5GHz
RAM: 16GB Kingston HyperX Predator @ 2400MHz
Motherboard: MSI Z77A-GD65
GPU: Sapphire HD7970 3GB GHz Vapor-X
CPU Cooler: Corsair H100i (Pull)
SSD 1: OCZ Vector 128GB
SSD 2: OCZ Agility 3 60GB
HDD 1: Seagate 2TB HDD
HDD 2: Samsung 500GB HDD
H100i Fans: Corsair SP120 x 2
Front Case Fans: BitFenix Spectre x 2
Rear Exhaust Fan, Under 5.25 Optical Bay Drives: Corsair AF140 x 2
HDD Fan Mount (Extra Cooling for GPU): Corsair AF120
Case: Corsair Carbide 500R

I know the 500R Comes with a Mesh Side, but I plan on removing that and adding some Acrylic in there for a side window.

I did decide on an XFX 850W XXX Edition, but I have read that it would be a good idea to get at least 88% efficiency out of your PSU. However, I know I will be also powering my Mouse, Keyboard, Blue Snowball and other things out of the USB Ports. Also, I'm thinking of getting a LCD Fan Controller too and I could be getting another PCIe X1 card to put in.

Do you reckon 850W is enough and from XFX? I currently have one of their GPU's but the fan does make a loud noise when loaded! (Even though I have come to grips with it now.)

So I'm debating on an 850W from XFX, SeaSonic 750W or any other branded PSU, but not too sure, though it has to be modular. What would you all recommend?

Regards,

Kieran

More about : choosing correct wattage psu build

a b ) Power supply
April 12, 2013 3:22:01 AM

i'd grab the seasonic. best psu maker out there right now.

and 500W is enough for your build, 750 should be enough to let you xfire that gpu down the road if that's your ultimate goal.
m
0
l
April 12, 2013 3:25:41 AM

ingtar33 said:
i'd grab the seasonic. best psu maker out there right now.

and 500W is enough for your build, 750 should be enough to let you xfire that gpu down the road if that's your ultimate goal.


Thankyou for your quick reply!

Really 500W? I thought with all of that, I'd need at least 850W, to give me some room for adding further cards and fan controllers. Plus I plan on overclocking both my CPU and GPU too. But if I can get away with a 500W PSU then wow! Money saved! But I will probably get a 750W, as you said just incase if I XFire and I know that I have spare room to add more parts if I need!
m
0
l
Related resources
a b ) Power supply
April 12, 2013 3:33:54 AM

KieranThePCGuy said:
Thankyou for your quick reply!

Really 500W? I thought with all of that, I'd need at least 850W, to give me some room for adding further cards and fan controllers. Plus I plan on overclocking both my CPU and GPU too. But if I can get away with a 500W PSU then wow! Money saved! But I will probably get a 750W, as you said just incase if I XFire and I know that I have spare room to add more parts if I need!


Just as an FYI, my 3570K@4.1ghz, 8GB, GTX670, 2x7200 and 1xSSD barely pull 300 watts from the wall. My PSU is 85% efficient or so, making the actual power supplied about 255 watts. If you don't plan on doing Crossfire/SLI and you have new gear like you listed then pretty much any machine can be run on a good quality 500w PSU.

Over at Anand's test bench they list the 7970 machine (which is a pretty beefy test rig) as pulling a peak of 391watts from the wall. I believe they use a 90% efficient PSU making the actual delivery about 350 or so. Again, comfortable for any good quality 500.

Gone are the days of the 200watt CPU and 350w video cards.

m
0
l
April 12, 2013 3:40:59 AM

Traciatim said:
KieranThePCGuy said:
Thankyou for your quick reply!

Really 500W? I thought with all of that, I'd need at least 850W, to give me some room for adding further cards and fan controllers. Plus I plan on overclocking both my CPU and GPU too. But if I can get away with a 500W PSU then wow! Money saved! But I will probably get a 750W, as you said just incase if I XFire and I know that I have spare room to add more parts if I need!


Just as an FYI, my 3570K@4.1ghz, 8GB, GTX670, 2x7200 and 1xSSD barely pull 300 watts from the wall. My PSU is 85% efficient or so, making the actual power supplied about 255 watts. If you don't plan on doing Crossfire/SLI and you have new gear like you listed then pretty much any machine can be run on a good quality 500w PSU.

Over at Anand's test bench they list the 7970 machine (which is a pretty beefy test rig) as pulling a peak of 391watts from the wall. I believe they use a 90% efficient PSU making the actual delivery about 350 or so. Again, comfortable for any good quality 500.

Gone are the days of the 200watt CPU and 350w video cards.



Wow, is that it?! I've been lead to believe I would need at least 850W for all of that, I used a PSU Wattage Calculator and that said about 825W roughly.

So even if I was to overclock my CPU and GPU, and add further cards, HDD's and fan controllers, I would only need about 550W?

I don't plan on XFire'ing, just stick with the one card and hopefully the rig lasts me a good 5 - 6 years! :p 
m
0
l
a b ) Power supply
April 12, 2013 3:53:30 AM

well... part of why i didn't really suggest you back off the 750W PSU is because i don't know the type of overclocking or future upgrading you might be into. The cpu really doesn't matter, it won't eat a lot of power no matter what you do on the overclock front... but the GPU? a 7970 can guzzle power when overclocked.

I'd say 550W is the smallest psu i'd stick on that machine. a high quality 550W psu should handle whatever overclocking or other junk you toss onto that system (especially if you're not planning on xfiring your gpu)
m
0
l
April 12, 2013 3:56:44 AM

ingtar33 said:
well... part of why i didn't really suggest you back off the 750W PSU is because i don't know the type of overclocking or future upgrading you might be into. The cpu really doesn't matter, it won't eat a lot of power no matter what you do on the overclock front... but the GPU? a 7970 can guzzle power when overclocked.

I'd say 550W is the smallest psu i'd stick on that machine. a high quality 550W psu should handle whatever overclocking or other junk you toss onto that system (especially if you're not planning on xfiring your gpu)


I'm not going to back off the 750W PSU buddy, I think I'm going to get that as then I have room for expansion and OC'ing headroom! So I think I am going to stick with the 750W PSU, Just got to look for which one now! Ha! Thanks!

m
0
l

Best solution

a b ) Power supply
April 12, 2013 3:59:49 AM

He forgot to mention that 7970 Ghz consumes more than GTX 670 . Actually the 7970 @1100 need ~340W at max load and normally from 250-300W mark. So if you plan to CF 500W is an absolute 0 .

Only the 2 beasts need ~520W on CF on the 12v Rail. So a 750 W unit would be ok :) 

I would personally choose the corsair too :) 
Share
April 12, 2013 4:14:29 AM

prototype18 said:
He forgot to mention that 7970 Ghz consumes more than GTX 670 . Actually the 7970 @1100 need ~340W at max load and normally from 250-300W mark. So if you plan to CF 500W is an absolute 0 .

Only the 2 beasts need ~520W on CF on the 12v Rail. So a 750 W unit would be ok :) 

I would personally choose the corsair too :) 


Thanks for the info! It's decided I will go for a 750W from Corsair! Thanks everyone for your help! :D 
m
0
l
a b ) Power supply
April 12, 2013 4:18:57 AM

Np :)  Glad i helped you !
m
0
l
!