620 watts enough?

[phatthefirst]

Hi guys, i was wondering, with a 620 watt Antec Neo Eco, will I be able to power two Nvidia GTX 560's with the use molex to PCI connectors? Or will that be pushing the limit? Thanks.

PS: My Build

CPU: Core i5 2500
GPU: Gigabyte GTX 560 OC ( thinking of getting 2, hence the thread)
Mobo: MSI p67a GD-55
HDD: Caviar black 500gb
RAM: G.skill 4gb 1600mhz

+ 7 case fans (1 with LED)

thanks again.

 

[davcon]

You'd be pushing the limit.
A high quality 650W with 4 supplied pcie connectors would be better.
http://www.guru3d.com/article/geforce-gtx-560-ti-sli-review/14
This unit is often on sale if you look around.
http://www.newegg.com/Product/Product.aspx?Item=N82E16817371021
This also delivers much more then the labelled output.

 

[ghnader hsmithot]

Not sufficient.

second card requires you to add another ~175 Watts. You need a 700+ Watt power supply unit if you use it in a high-end system (800+ to a KiloWatt is recommended if you plan on any overclocking).
For each other card (3-way SLI) that you add, just add another 200 Watts and 20A on the 12V rails as a safety margin. What would happen if your PSU can't cope with the load? Here are some pointers:

bad 3D performance
crashing games
spontaneous reset or imminent shutdown of the PC
freezing during gameplay
PSU overload can cause it to break down

http://www.guru3d.com/article/geforce-gtx-560-ti-sli-review/14

 

[davcon]

A quality 650W psu would be fine.
He has a Core i5 2500 not an overclocked i7 965 as used in the review.
Big difference + two GTX 560's only used 300W at full power.

 

[phatthefirst]

yeesh, the thing is, my budget isnt big. I can't afford a new PSU. so i guess it's still only one GPU then. I used this
http://extreme.outervision.com/psucalculatorlite.jsp

just to get a rough idea. i know people say it is unreliable, so by rough, i mean very rough. 610 Watts, apparently.

Now it puts the estimate if all components are at 90% load, which they probably won't be at. so now im stuck. I'll just be waiting for more replies, i guess.

 

[phatthefirst]

BTW is my PSU a 'quality' one, like you guys say?

 

[davcon]

You can't add another gpu on your current power supply.
One GTX 560 requires 30A of power.
Your psu has only 48A total on the 12V rail.
A good 650W psu like the Antec TPN -650W would run 2x560 no problem.
You need a psu that has 60A or more on it's 12V rails.
There's plenty of people running 2xGTX 560's with high-end 650W psu's.

 

[davcon]

BTW is my PSU a 'quality' one, like you guys say?

Yes it's a good quality unit and excellent for one gpu.
Unfortunately it's underpowered for 2 GTX 560's.

 

[diellur]

I second the link zulfadhli posted - if it wasn't there, I'd have posted it myself.

I've got more or less the same build as you (processor, GPU, RAM) and plan on SLIing in the future. I've got a 750W supply and, when I OC, I'm not sure if it'll be enough. 650W may do it, but it's probably worthwhile in sinking an extra few quid into a more powerful PSU now than having to get a whole new one later on.

 

[phatthefirst]

hey guys, thanks a lot for replying. i didn't even consider the amps part. thanks so much again. i'll be sticking to one GPU then.