# Minimum Power Supply Wattage?



## JACarter (Oct 6, 2012)

Intel Core i5-3550 Ivy Bridge 3.3GHz
ASUS P8Z77-V LK LGA 1155 Intel Z77 HDMI SATA 
EVGA GeForce GTX 560 Ti (Fermi) 2GB 
Optical/Bluray Drive
SSD & HDD
8gb RAM


I currently have a 550w PSU. Just wondering if that is enough.


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## greenbrucelee (Apr 24, 2007)

Its 500w *BUT* it isn't just about wattage it is about quality. A low quality power supply that has enough power can do more damage than a good quality psu with not enough power toa system.

Anything made by seasonic which include seasonics own,corsair (not the GS or CX models though) and xfx are top quality.

You should also be aware that going for the minimum recommended psu is not advisable you should really add 30% to what it says for the minimum wattage so 500 + 30% = 650w

The psu is the most important part of your system go cheap or go crap (usually go together) means you will end up with problems at some point and when low quality power supplies die they tend to damage other parts of the system such as the graphics card, RAM and motherboard but they can damage everything when they die.


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## JACarter (Oct 6, 2012)

Thank you.
I currently have a 550w OCZ Fatal1ty PSU. I've had it running in a Dell Inspiron 560 with a Radeon HD 5850 and 6gb RAM for about a year with no problems what so ever.
What would you or anyone else recommend if it still isn't acceptable.


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## greenbrucelee (Apr 24, 2007)

a 650w made by seaonic or any that seasonic make such as corsair TH, TX and AX models or xfx pro.

You will be able to run with that psu but you stand a very good chance of it dying and OCz dont make great power supplies so when it dies there is a chance it could damage your system.


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## JACarter (Oct 6, 2012)

Thank you for your help, you've persuaded me.
Like most people budget is a big thing. I'm wanting to stay under $100 if possible.

Something such as:
Newegg.com - SeaSonic M12II 620 Bronze 620W ATX12V V2.3 / EPS 12V V2.91 SLI Ready 80 PLUS BRONZE Certified Modular Active PFC Power Supply


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## Tyree (May 10, 2009)

That PSU "should" be good for your system but a 650W would be better: Newegg.com - XFX Core Edition PRO650W (P1-650S-NLB9) 650W ATX12V 2.2 & ESP12V 2.91 SLI Ready CrossFire Ready 80 PLUS BRONZE Certified Active PFC Power Supply


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## greenbrucelee (Apr 24, 2007)

agreed there is a difference between 650 and 630w. These are not made up safe figures. Just because you get the best of the best for your psu if its 620 and you need 650 you may damage it or it may damage your system..


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## Wrench97 (May 10, 2008)

A 620w is more then enough to run a 560ti card.


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## MPR (Aug 28, 2010)

Don't just look at the stated total power rating when determining which PSU caan power a certain video card -- look at the number and amperage of the 12 V rails and the amperage required by the card.

For instance, the GTX 560 Ti requires 30 Amps continuous current @ 12 V. Below are the specs for the 550w OCZ Fatal1ty PSU:

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Note that while the total amperage is sufficient, there is a possibility that if the power is not distributed correctly that a video card requiring 30 A could cause the overcurrent protection to shut the system down under load if it pulls most of its power from a single rail.

It's difficult to determine which power connectors come from which rail unless the manufacturer or reviewer who has disassembled the PSU posts the information. You can check to see if the PSU is NVIDIA SLI certified -- if it is then the PCIE connectors probably come off different rails. 

While you can mess around with connections, and perhaps even use molex-PCIE adapters to split the current load between the rails, it's much simpler to just purchase a PSU that can provide the amperage required from a single high-power rail. The PSU Tyree linked supplies 53 A on a single 12 V rail.


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## JACarter (Oct 6, 2012)

Thank you guys for the help.

My current OCz PSU is Nvidia SLI certified. While I don't want to cheap out on a PSU I really don't want to spend $100 on one. :nonono: I'm sort of getting mixed answers, at least from my understanding, and kind of confusing. So pretty much the set PSU I'm looking for is atleast 650w and at least 30+ Amps on a single rail?
Would there be any other recommendations, possibly cheaper.


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## pctoxicated (Sep 22, 2012)

Newegg.com - CORSAIR Enthusiast Series TX650 V2 650W ATX12V v2.31/ EPS12V v2.92 80 PLUS BRONZE Certified Active PFC High Performance Power Supply
89.99
69.99 after rebate


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## JACarter (Oct 6, 2012)

On a new note:
Although I stated about the GTX 560 ti, I think I'm going to go with a GIGABYTE Radeon HD 7870 instead. Price aside, what would be the recommended Wattage and Amps on the 12v rail.
Also, someone care to explain how to get these results so I can actually learn something and not to keep asking. 
Thank you.


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## MPR (Aug 28, 2010)

Don't fall into the trap of spending hundreds on high-end components only to try to power them with low-end or mediocre PSUs. When building or upgrading a system the PSU should be budgeted before anything else as it is the "heart" of your system. Your OCZ, while not the worst PSU in the world (my vote is for Diablotek), is neither the best and also provides the bare minimum of power for the cards you are selecting.

Though the 7850 has a bit lower power needs than the 560 Ti, you are still on the cusp of the minimum power requirements. Both video cards can probably be used with your current PSU but you will have no little or no redundancy. When when the components in your PSU and system begin to degrade (and they will) there is the distinct possibility that the PSU will fail and take your GPU or other components of the computer system with it.


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## Wrench97 (May 10, 2008)

Use the recommended Power Supply Calculator here> eXtreme Outer Vision - eXtreme tools for computer enthusiasts


```
System Type:		1 physical CPU	
Motherboard:		High End - Desktop	
CPU Socket:		Socket LGA 1155	
CPU:		Intel Core i5-3570 3400 MHz Ivy Bridge	
CPU Utilization (TDP):		90% TDP	
			
RAM:		4 Sticks DDR3 SDRAM	
Video Card 1:		AMD Radeon HD 7870	

			
Regular SATA:		2 HDDs	
			
DRAM SSD:		1 Drive	
DVD-RW/DVD+RW Drive:		1 Drive	
Blu Ray BD-RE/DVD/CD:		1 Drive	
			
Sound Blaster - All Models:		Yes	
PCI-e x1 Card:		1 Card	
			
USB:		6 Devices	
			
Fans			
LED: 		3 Fans 120mm;  	
			
Keyboard and mouse:		Yes	
			
System Load:		90 %	
			
Capacitor Aging (+ W %):		30 %	
			
 
Minimum PSU Wattage:		475 Watts	
Recommended Wattage:		525 Watts
```
Quality of the supply is as, if not more important then the wattage once the recommended size is reached.


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## Tyree (May 10, 2009)

The 7870 requires the same power as the 560 ti.
500W is the recommended minimum of the both chipset manufacturer's. 
The simple and sure way to insure sufficient power is add 30% to the manufacturer's recommended number, use only top quality PSU's, and you can't go wrong.
500W + 30%=650W.


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## Wrench97 (May 10, 2008)

30% is added to the required wattage when you figure it out by individual component usage, not to the recommended since we have no idea what they have used for the calculation or what has been added in.
In most cases it's a fairly high spec system and the Capacitor aging factor is already added in. As shown by the above example.


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## JACarter (Oct 6, 2012)

Alright, thank you guys. 

650w it is.


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## Tyree (May 10, 2009)

Good choice and you will be assured you have sufficient power for extended use with 650W unit.


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