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PLEASE READ ! THIS IS HOW YOU DETERMINE THE PSU POWER REQUIRED

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a b à CPUs
September 29, 2011 12:14:32 AM

You can determine exactly what your current or future PC configuration will require for wattage and amps. on the 12v rail(s) by working thru the information below. You start by checking the Video Graphics card wattage then convert that to 12v rail(s) amps. and check out PSU reviews to see if your current or potential new PSU can deliver the amps. you need on the 12v rails. It's pretty easy and once you know how to do it you'll be in a position to not only help yourself but also help other folks learn. These tools will make your PC user experience better and more reliable.

There are several websites that show the Graphics card Max power consumption in watts. (See the links below). Divide the watts by 12 to determine the amps. required on the 12v rail(s). Add 15 amps for the rest of the PC on the 12v rail and you now know the Minimum total 12v rail amps required under full load. It's best to have at least 5-10 amps. minimum reserve on the 12v rail(s) available under full load so the PSU is not loaded to 100%.

Here's an example:

Say your Vid card draws 240W under max load. Divide 240 by 12 to get 20 amps. on the 12v rail. Add 15 amps. for the rest of the drives, fans, etc. and you have 35 amps. Add 5 more amps for a minimum safety margin when the PSU gets hot under full load and you end up needing <40+> amps. total on the 12v rails.

If your PSU has a single 12v rail and it delivers 40+ amps. under full load then you are in good shape. If not you need a better/larger PSU. If you have a multi-rail 12v PSU then you need to check the label to see what the combined amps output is for the 12v rails under max load. If it's 40+ amps. combined, then you're good to go. If not then you need a better/larger PSU. The individual 12v rail max amps. may NOT be the same as the combined 12v rails max amps, so check the label and read proper PSU reviews to confirm the PSU is quality built and can deliver the claimed amps. under max load and temps. This is important for stable PC operation.

240W/12 = 20 amps + 15 amps. for the rest of PC + 5 amps. safety margin = 40+ amps. Minimum required

http://www.guru3d.com/article/geforce-gtx-560-ti-sli-re...

http://www.techpowerup.com/reviews/NVIDIA/GeForce_GTX_5...

As far as PSUs are concerned, be informed. Before you buy any PSU, read accurate, objective PSU reviews at reputable sites such at Toms', www.jonnyguru.com or www.hardwaresecrets.com on the EXACT model PSU that you are interested in as some brands have good and poor quality PSUs.

It's also worth noting that people often misunderstand the 80% power rating. This is a rating of the PSU's energy efficiency not it's output. 80% plus PSUs use less grid power to produce the same PC power. If it's 80% Bronze, Silver or Gold the cost savings on electricity is pretty small between Bronze, Silver and Gold models unless you are paying very high rates for electricity thus any 80% rated quality PSU is likely to be fine even if not Gold. For those who leave their PC on 24/7 a quality 80% PSU is a good investment.

For a basic PSU calculation you can determine the total power (wattage), required for your current or future system at the PSU calculator link below. Once you know the total PSU watts required then you need to confirm that the 12v rail(s) has enough amps. to support your Graphics card(s) and the rest of the PC system as shown above in the calculation example.

http://extreme.outervision.com/psucalculatorlite.jsp

IT'S ALWAYS BETTER TO TEACH A PERSON HOW TO FISH THAN TO GIVE THEM A FISH FOR DINNER!

KNOWLEDGE IS POWER. INVEST SOME EFFORT IN LEARNING SO THAT YOU CAN NOT ONLY HELP YOURSELF BUT OTHER FOLKS TOO.
a c 161 à CPUs
September 29, 2011 1:00:04 AM

Added it to the PSU sticky and got rid of the duplicates. I will add it to other appropriate stickies as needed, but now you have a nice one to link back to so you dont need to copy paste anymore, and we can help to improve it.
Related resources
a b à CPUs
September 29, 2011 3:36:32 PM

oh finally............
a b à CPUs
September 29, 2011 4:49:12 PM

anyone want to run a sweepstake on how many, can my psu run... questions we still get.
a c 103 à CPUs
September 29, 2011 4:53:21 PM

This is cool, but the lazy majority who post 'can I power xxx' threads dont want to work things like numbers out, they want a yes/no answer with minimal details
for folks in the know its a handy reference tool so all thanks for that man,
but we will still see the posts I fear
**Edit, but I'll just post them this link haha (Evil mode: On)
Moto
September 29, 2011 8:49:29 PM

oh no, i just posted my " what psu do i need " then i saw this...
October 23, 2011 12:56:31 AM

Same here! :pt1cable: 
But to be honest, I'd rather get an answer from the community since I value what the people from Tom's Hardware have to say. Besides, people answer if they want to, nobody's forcing anyone, and it should feel nice to help someone in the form of a simple answer. :D 
I must admit that these links offer a good read, thank you!
:hello: 
October 27, 2011 2:57:45 AM

thanks :)  this help me alot :D 
October 28, 2011 1:15:32 AM

Really helpful. Using this I was able to decide if I could power two gtx 570s. Not listen to one person say yes, while the other say no :) 
a b à CPUs
November 6, 2011 11:00:12 PM

Glad to help folks. Many people ask the same or similar question and with the tutorial/Utilty you can objectively determine what you need and whick PSUs are quality units that can deliver the power.
November 7, 2011 3:36:45 AM

hey anyone know how much power I need for my new gaming rig???

anyone...anyone?
November 10, 2011 3:58:52 AM

beenthere said:
You can determine exactly what your current or future PC configuration will require for wattage and amps. on the 12v rail(s) by working thru the information below. You start by checking the Video Graphics card wattage then convert that to 12v rail(s) amps. and check out PSU reviews to see if your current or potential new PSU can deliver the amps. you need on the 12v rails. It's pretty easy and once you know how to do it you'll be in a position to not only help yourself but also help other folks learn. These tools will make your PC user experience better and more reliable.

There are several websites that show the Graphics card Max power consumption in watts. (See the links below). Divide the watts by 12 to determine the amps. required on the 12v rail(s). Add 15 amps for the rest of the PC on the 12v rail and you now know the Minimum total 12v rail amps required under full load. It's best to have at least 5-10 amps. minimum reserve on the 12v rail(s) available under full load so the PSU is not loaded to 100%.

Here's an example:

Say your Vid card draws 240W under max load. Divide 240 by 12 to get 20 amps. on the 12v rail. Add 15 amps. for the rest of the drives, fans, etc. and you have 35 amps. Add 5 more amps for a minimum safety margin when the PSU gets hot under full load and you end up needing <40+> amps. total on the 12v rails.

If your PSU has a single 12v rail and it delivers 40+ amps. under full load then you are in good shape. If not you need a better/larger PSU. If you have a multi-rail 12v PSU then you need to check the label to see what the combined amps output is for the 12v rails under max load. If it's 40+ amps. combined, then you're good to go. If not then you need a better/larger PSU. The individual 12v rail max amps. may NOT be the same as the combined 12v rails max amps, so check the label and read proper PSU reviews to confirm the PSU is quality built and can deliver the claimed amps. under max load and temps. This is important for stable PC operation.

240W/12 = 20 amps + 15 amps. for the rest of PC + 5 amps. safety margin = 40+ amps. Minimum required

http://www.guru3d.com/article/geforce-gtx-560-ti-sli-re...

http://www.techpowerup.com/reviews/NVIDIA/GeForce_GTX_5...

As far as PSUs are concerned, be informed. Before you buy any PSU, read accurate, objective PSU reviews at reputable sites such at Toms', www.jonnyguru.com or www.hardwaresecrets.com on the EXACT model PSU that you are interested in as some brands have good and poor quality PSUs.

It's also worth noting that people often misunderstand the 80% power rating. This is a rating of the PSU's energy efficiency not it's output. 80% plus PSUs use less grid power to produce the same PC power. If it's 80% Bronze, Silver or Gold the cost savings on electricity is pretty small between Bronze, Silver and Gold models unless you are paying very high rates for electricity thus any 80% rated quality PSU is likely to be fine even if not Gold. For those who leave their PC on 24/7 a quality 80% PSU is a good investment.

For a basic PSU calculation you can determine the total power (wattage), required for your current or future system at the PSU calculator link below. Once you know the total PSU watts required then you need to confirm that the 12v rail(s) has enough amps. to support your Graphics card(s) and the rest of the PC system as shown above in the calculation example.

http://extreme.outervision.com/psucalculatorlite.jsp

IT'S ALWAYS BETTER TO TEACH A PERSON HOW TO FISH THAN TO GIVE THEM A FISH FOR DINNER!

KNOWLEDGE IS POWER. INVEST SOME EFFORT IN LEARNING SO THAT YOU CAN NOT ONLY HELP YOURSELF BUT OTHER FOLKS TOO.



sorry brother i didnt understand it .

my system i5 2500k + gigabyte GA h67 + GTX 560 ti + 2 sata hdd + 2 sata dvd writer

for this sys which psu is good

whether corsair cx500 or corsair cx600 will good option ?? ( not going to use sli / crossfire )
or should i go for corsair GS series ?? (will GS 500 will able to good than corsair cx500/cx600) ????
a b à CPUs
November 10, 2011 5:25:00 AM

swapnilbunty123 said:
sorry brother i didnt understand it .

my system i5 2500k + gigabyte GA h67 + GTX 560 ti + 2 sata hdd + 2 sata dvd writer

for this sys which psu is good

whether corsair cx500 or corsair cx600 will good option ?? ( not going to use sli / crossfire )
or should i go for corsair GS series ?? (will GS 500 will able to good than corsair cx500/cx600) ????

Antec Neo 620w for single and the Corsair 800w for sli. That should me more than enough
!