Help in picking a psu

[Fallin]

Hello everyone,

This is my first time in the community. I usually search through the forums to find my answer, but I need some help. I want to get a psu.

I'm building a brand new pc. I was thinking of going with either a full tower or mid tower. I will use it for gaming what kind of power supply should I get? I plan getting an Intel 2600k, I'm not sure on Motherboard quite yet I was thinking maybe getting the ASUS p8z68-v Pro gen 3. For video card it will be amd just not sure what i'm going to get and it will be only one video card for now. It will have 2 hard drives, 2 cd burners, and a card reader and I'm going to put in at least 16 gigs of ram. If you need more info let me know. Any advice would be very much appreciated.

Thanks in Advanced

 

[geofelt]

The psu you need is almost entirely determined by the graphics card you pick. That is assuming a normal complement of a few hard drives, fans, dvd's, overclocking, etc.

Here is what EVGA recommends for their graphics cards:

GTX550ti needs 400w with 24a on the 12v rails plus one 6-pin PCI-E power lead.

GTX560 needs 450w with 24a on the 12v rails plus two 6-pin PCI-E power leads.

GTX560Ti needs 500w with 30a on the 12v rails plus two 6-pin PCI-E power leads.

GTX570 needs 550w with 38a on the 12v rails plus two 6-pin PCI-E power leads.

GTX580 needs 600w with 42a on the 12v rails plus one 6-pin and one 8-pin PCI-E power lead.

GTX590 needs 700w with 50a on the 12v rails plus two 8-pin PCI-E power leads or 4 6-pin power leads.

Whatever you do, do not go cheap on the psu.
My short list of quality psu brands would include Seasonic, Antec, PC P&C, XFX, and Corsair.

If budget is an issue, the 2500K at $100 less is an equally good gaming cpu, and the $100 will get you better gaming when spent on a better graphics card.

 

[crimsonpc]

You said "one video card for now"... are you planning to add a second one later? If so, you should get a power supply that can run two of them.

 

[Fallin]

Whatever you do, do not go cheap on the psu.
My short list of quality psu brands would include Seasonic, Antec, PC P&C, XFX, and Corsair.

If budget is an issue, the 2500K at $100 less is an equally good gaming cpu, and the $100 will get you better gaming when spent on a better graphics card.

I was reading and heard from my friends the 2500k doesn't have hyperthreading. Would I need that hyperthreading, doens't that allow for better multitasking? If it won't really make a difference I could go with the 2500k and get a better graphics card.

With the XFX I was looking at the

XFX PRO850W XXX Edition Semi-Modular 80 Plus Silver Certified 850 Watt Active PFC Power Supply
What do you think of this one

Should I get a psu with full modular or semi? Do you really need a 80+ (silver, bronze, gold, ...)certified psu?

Sorry for all the questions. Thanks for the Evga recommendations that helps. My psu will be minimum 700w

 

[4745454b]

For video card it will be amd just not sure what i'm going to get and it will be only one video card for now.

Nice list of Nvidia power draw Geofelt...

As Geo mentioned however the PSU you should get really depends on the CPU and GPU that you use. There is no need for a 750W PSU if you'll be running a 95W CPU and two 6770s. (~100W power draw, so system with two cards would be around 350W) Figure out what GPU(s) you'll be running then you can pick the PSU.

edited to fix quote.

 

[Fallin]

You said "one video card for now"... are you planning to add a second one later? If so, you should get a power supply that can run two of them.

I'm planning to get second one. So 700 watts might not be enough. If I did get 2 what would be the minimum wattage I get. Lets say I got 2 Radeon HD 6870 or 2 GeForce GTX 560s. What would the reccomandation for those. THanks.

 

[Fallin]

For video card it will be amd just not sure what i'm going to get and it will be only one video card for now.

Nice list of Nvidia power draw Geofelt...

As Geo mentioned however the PSU you should get really depends on the CPU and GPU that you use. There is no need for a 750W PSU if you'll be running a 95W CPU and two 6770s. (~100W power draw, so system with two cards would be around 350W) Figure out what GPU(s) you'll be running then you can pick the PSU.

edited to fix quote.

I think i'm a little lost i'm looking at the evga reccomendation and it says for the 560 gtx they reccomend 450, what if I wanted to make it 2. Do they always reccomend mor than what is needed. Cause if i'm looking at the pcie card link http://www.tomshardware.com/reviews/fastest-graphics-card-radeon-geforce,3067-4.html
it says the power requires 160 watts so that would be 320 for 2 plus 95 for cpu so would a 450 be good or do i need to go with a higher wattage psu?

 

[4745454b]

Your motherboard and drives will take some 12V power, so I'd round up to 500W. Add a little more headroom so you aren't running the PSU at 100%, and any quality PSU that can output 550W on the 12V rail(s) should be fine in that case. As you move up in GPUs however the power draw gets higher. If your GPUs need 250W, then 500W will only cover the GPUs and not the CPU or anything else.

Pick the GPUs and then decide on the PSU. Really the only way to go. As for HT, not really needed for games. They don't run on all available cores so a quad core is fine. And as mentioned, that $100 saved could be used on GPUs where it will make a difference.

 

[Fallin]

Your motherboard and drives will take some 12V power, so I'd round up to 500W. Add a little more headroom so you aren't running the PSU at 100%, and any quality PSU that can output 550W on the 12V rail(s) should be fine in that case. As you move up in GPUs however the power draw gets higher. If your GPUs need 250W, then 500W will only cover the GPUs and not the CPU or anything else.

Pick the GPUs and then decide on the PSU. Really the only way to go. As for HT, not really needed for games. They don't run on all available cores so a quad core is fine. And as mentioned, that $100 saved could be used on GPUs where it will make a difference.

So at the GPUs i'm looking at, minimum would probably 550 or 600 watts and If I go with the 2500k, that will save about 100$. I could use that to get better gpus and maybe go with a 650 or 700 watt power supply.

What does the modular do for a psu and why would you need HyperThreading?

Thanks.

 

[Fallin]

SeaSonic 750 watt
http://www.newegg.com/Product/Product.aspx?Item=N82E16817151087

PC P&C 750 watt
http://www.newegg.com/Product/Product.aspx?Item=N82E16817703027

PC P&C 950 watt
http://www.newegg.com/Product/Product.aspx?Item=N82E16817703028

Corsair 750 watt
http://www.newegg.com/Product/Product.aspx?Item=N82E16817139010

XFX 850 Watt
http://www.newegg.com/Product/Product.aspx?Item=N82E16817207017

I was looking at these. I wanted everyone's advise on which one ya'll think I should get. I'm pretty sure I want to get the asus p8z68 pro gen 3 motherboard with 2500k and 2 video cards. Not sure if im going AMD or GtX. I posted above what I'm looking at for video cards right now. If I go higher video card might be the 6950. Any advice would be appreciated. Thanks.

 

[4745454b]

The Corsair. If you are looking at those other GPUs however its still overkill. Really only need this if you go with CF/SLI'd 6950 or similar cards.

Edit: Forgot to mention I picked the Corsair because its the cheapest of the PSUs up there. You won't really go wrong with any of them.

 

[ko888]

The CORSAIR Professional Series HX750 (CMPSU-750HX), PC Power and Cooling Silencer Mk II 750W and the SeaSonic X750 Gold 750W, that you've linked to, are all fully capable of powering a system with two GeForce GTX 560 in SLI or two Radeon HD 6870 or two Radeon HD 6950 in CrossFireX.

My recommendation is also the CORSAIR Professional Series HX750 (CMPSU-750HX).

 

[geofelt]

To answer some questions:

1) The 2500K does not have hyperthreading.. true. A hyperthread uses residual cycles of the main core. That amounts to about 1/4 of a core, more or less.
Extra cores or hyperthreads are useful with multithreaded apps. But for games, which will use few cores, typically two or three, the extra threads are not very helpful. The extra cache on the 2600k is of unknown value in performance. If $100 is not that important to you, get the 2600K. As an early adopter, I got a 2600K. But, I have turned off hyperthreading, since I can see that I rarely use even the 4 full cores. Had I the option to do it again, I would have used a 2500K.

2) I find modular/semi modular non modular to be a non issue.

A semi modular psu will have fixed attachments for the power leads that are always used, like the 20 pin main lead, a 4/8 cpu lead, and perhaps a 6 pin pci-e connector. The others need not be attached if you don't use them.

On a non modular psu, you will probably be using most of the leads anyway. Unless you have a small form factor case, it will be no big deal to tuck those unused leads out of the way. Non modular advocates claim that modular leads lose power and may come loose. I doubt that is significant on a quality unit.

3) If I am not mistaken, a pci-e motherboard slot can deliver 75w or 6.25a to the grapnics card. If the card needs a single 6 pin connector, then that is another 75w or 6.25a. 8 pin connectors are more. So to size the psu increase for a second card, add 75w for the slot, and another 75w for a card that needs one 6 pin connector, or 150w for a card needing two. In this case, the second GTX560 will add 225w, so you would need a 675w psu. It is unlikely that the full limits of the slot and leads will be reached, but that is the conservative way to figure it.

4) Bronze/silver/gold is an efficiency rating. If you pay your own electricity bill, better efficiency is good. Perhaps more important is that you will generate less heat and have quieter operation with more efficient psu's. I used a gold rated Seasonic X750 in my small form factor case for just this reason. Even with a GTX580, the fan does not need to turn on.

5) I think graphics vendors suggest stronger psu's than are actually needed. In part to allow for poor quality psu's that do not deliver advertised power. A substandard psu can make it look like the graphics card is defective, and graphics card vendors don't want to deal with rma's for that reason. I have no problem using their overstated requirements. A slightly stronger than needed psu will operate more efficiently and quieter if it is not at max load.

6) For your needs, any of the 5 psu's you listed would be excellent.

 

[Fallin]

Best answer selected by Fallin.

 

[Fallin]

I want to thank everyone for all their help. I really appreciate it.

geofelt thanks for all the info you provided. This really help me to better understand. I really do appreciate all the knowledge you given us. Thanks.