Recommend minimum PSU wattage with water cooling and overclocking?

[Rob94hawk]

I haven't decided on a GPU yet but the parts I have so far are i7 3770k/Z77A-GD65/Corsair Vengance 8GB. Once they are in stock someday I will order the Swiftech H220.

What's the minimum wattage do you think I should go with? 850? Higher? Corsair? Seasonic? Thanx

[prava]

It all depends on the gpu cards you get, but 850W will probably on the highest you should get, if you were going dual titans or dual 690's. If you go with dual GTX680 or GTX670 you could do with 650-700W.

[lowfat]

If you are going w/ Kepler then 500W will honestly be fine. A 3570k @ 4.5GHz and GTX680 SLI @ 1200/3000 pulls 500W from the wall in my system. Assuming 90% efficiency that is about 450W of DC power used by the PSU.

So either way 850W would be plenty for any modern dual GPU setup.

[AMDforME]

I haven't decided on a GPU yet but the parts I have so far are i7 3770k/Z77A-GD65/Corsair Vengance 8GB. Once they are in stock someday I will order the Swiftech H220.

What's the minimum wattage do you think I should go with? 850? Higher? Corsair? Seasonic? Thanx

There are numerous online PSU size calculators with varying levels of accuracy. The link below is the best online PSU calculator that I have seen as it allows you to input pretty much all practical PC combinations. IME it is quite accurate if you input the proper information.

http://www.extreme.outervision.com/p...ulatorlite.jsp

Newegg and others also have online PSU calculators but they are not quite as accurate IMO as they tend to add more safety margin than the link above which allows you to decide how much safety margin you desire for possible future builds..

http://images10.newegg.com/BizIntell...alc/index.html

As far as PSU brand, IME Seasonic offers the best performance, quality and price. Some companies like Corsair and others buy a version of a Seasonic or other brand of PSU, which is not necessarily the same quality or performance as a similar wattage Seasonic PSU and then sell it under their own brand name. If you buy the Seasonic direct then you know that you are getting the best PSU without any "cut corners" to save a few $$$. Other than the Seasonic brand, PSU brand alone does not guarantee that the PSU is the top quality equivalent available from Seasonic.

There are some other brands that do offer a quality PSU but you need to look at objective test data from Jonnyguru.com or similar reputable review sites to know if the exact PSU model you are considering really is a quality PSU at a good price.

http://www.jonnyguru.com/

One last point on PSU power size selection...the total PSU wattage is not as important on a newer PC build in the past 10 years as is the 12V rail(s) total amperage, aka "amps". You can add up the max 12v rail amps required for a PC system, which is primarily the mobo/CPU, drives, fans and GPU card and that will tell you what the PSU 12v rail(s) must provide for amps.

[lowfat]

There are numerous online PSU size calculators with varying levels of accuracy. The link below is the best online PSU calculator that I have seen as it allows you to input pretty much all practical PC combinations. IME it is quite accurate if you input the proper information.

http://www.extreme.outervision.com/p...ulatorlite.jsp
.

This is telling me 721W when I know that is is using less than 500W under full load. So I wouldn't say it is all that accurate either IMO.

[Conumdrum]

Watercooling adds very little wattage. 20ish watts for the pump and a few fans over a normal air setup. Why are you even asking this in the WC forum?

Maybe you need to learn about watercooling first.

[zeroibis]

I wish the option for fans was higher 10 is not nearly enough... but yea the http://www.extreme.outervision.com/p...ulatorlite.jsp is pretty accurate.

[Rob94hawk]

Watercooling adds very little wattage. 20ish watts for the pump and a few fans over a normal air setup. Why are you even asking this in the WC forum?

Maybe you need to learn about watercooling first.

^^This quote is funny!

[Conumdrum]

And why so funny? It's talked about and part of learning about WC.

[madmaxx]

A quality 750w/850w unit should do you just fine! You'd be in the PSUs "sweetspot" and it will give you room to add on in the future and also help guard against capacitor failure if you intend to keep the system for a while. If you scooped up a platinum rated unit you could prolly get away with a 650w. I always use the extremeoutervision calc and it has never let me down! I like how i can select OC, 100% Load & factor in capacitor aging into the equation

[AMDforME]

This is telling me 721W when I know that is is using less than 500W under full load. So I wouldn't say it is all that accurate either IMO.

If you input the correct info. you get the correct output. That includes the percentage used for capcitor aging, future upgrades and safety margin so that the PSU is not operating at 100% when the current system is at full load. An ~20% reserve (minimum), is considered normal, without any consideration for capcitor aging.

So if your max true load is 500w, then you'd typically use at least a 600W PSU, (500 x 1.2), without any considertion for capacitor aging or future upgrades that may require additional power above your current set-up.

With capacitor aging and future upgrades 700W would be a more realistic number if you desire to future-proof your system and/or get maximum value from your PSU purchase over a longer period of time vs. needing to buy another new, larger capacity PSU in 3-4 years.