PSU question...adding another 780ti sc to my pc

[VISUAL360]

Hello

I need some advice on PSU requirements. I already have a 780ti sc for rendering and a gtx 760 for my two 27" monitors.

Recently, I picked up another 780 ti sc and want to have the two of them solely dedicated to octane rendering.

I have a Seasonic 1250 and now concerned if that's enough power. If not, can I just purchase let's say another 800w Psu and just connect power to those two cards outside my machine and feed cables into those cards?

I don't think my nzxt h630 case has a place for the additional Psu.

Thanks for your help in advance! Enjoy the weekend

[smicha]

1250W PSU is more than enough for 3xGTX780TI, actually it can handle 4x780TI. I have 3x780+TITAN + water cooling stuff and on 25% overclock the system draws about 1000W.

[VISUAL360]

Thanks simcha for the almost instantaneous reply!

Now I can enjoy my weekend!!!!!

[glimpse]

1250W PSU is more than enough for 3xGTX780TI, actually it can handle 4x780TI. I have 3x780+TITAN + water cooling stuff and on 25% overclock the system draws about 1000W.

it's very interesting, seems that Octane on the load is using less power than some other applications like games =) in some cases synthetic stress tests under full load can tax nearly 300W from gk110 based cards..- so even if octane might be fine, just keep in mind that some application might stress your power supply a bit too much.. (just some information =)

I'd say bigger power supply isn't a waste, as it probably be more efficient, pluss those that regular fan speed based on load/heat will run less noisy & remember simple thing that good stable power supply is crucial to stability of entire system =)

[VISUAL360]

Thanks glimpse

How would one check power consumption when referring a scene?

Also, if the two 780ti cards are for rendering only, what priority setting makes sense in this case

...and could I tap into the gtx 760 if I wanted to or would that diminish the effect of the other two cards?

Really enjoying octane and the forum. Learning quite a bit here

[VISUAL360]

That's rendering a scene not referring!

[glimpse]

770 is rebranded, slightly reworked 680, while 760 & 670 are smaller siblings. I own 670 & I have TitanBlack, so I could say first hand that if You enable 760, You'll probably get like 20% boost in terms of performance over running 2x 780Ti =)

now about those active & priority check boxes, honestly I haven't noticed any difference with priority mode..so I can't comment (maybe it's hardware related..) anyway, I almost always now use to power screen from iGPU or dedicated screen card, that I don't do rendering on, just to have as fluid UI & other programs =)

now is it worth to enable 760? I think it depends on what card You have =) remember that You're limited to card having smallest amount of vram, as scene should fit in every card, so if You have 3gb 780Ti & rendering bigger scene, but only have 2 Gb of vram at your 760, that is consumed by monitor usage too..so I wouldn't bother to turn it on for rendering at all..but if You test scene is small enough & You stepping away from computer, why not? =) 20% is not that small of a difference..

[smicha]

Yes, Glimpse cautions are wise. Peak power draw might be much higher in games/other than octane usage. My power usage meter shows that my max draw was 1506W (my PSU can handle such peaks). If you want to monitor your power usage there are pretty cheap devices for about 10EUR. Go to ebay and search for 'power usage meter'.

[VISUAL360]

Thanks for the additional info. I will look into that device to watch over power draw.

Much appreciated.

[VISUAL360]

Smicha

Is this something like you mentioned