Sli performance question

[Rick Kraster]

Hello guys,

Since i have never run a Sli setup before i have a question about which card to run first(monitor) or if that matters at all.

Card 1 EVGA GTX 780 Ti SC reference cooler
Card 2 EVGA GTX 780 Ti SC acx cooler <-- Slightly faster

They both will be water cooled but not overclocked at this moment

 

[JamesLeaverland]

Hey !

It doesn't matter but if you're OCD like me put it in the first one

 

[Eggz]

It's whichever is plugged into your primary PCI-e slot, which is usually the one closest to the CPU. Doesn't matter which card is in there.

Faster cards will automatically underclock to the slower card unless you overclock the slower card to match the faster one (or both to an identically higher speed).

 

[azzazel_99]

I would run the acx evga in the top slot and put the monitor on that gpu. The reference cooler exhausts out the back and not back into the case so have that below the acx will be the best placement.

 

[Eggz]

???

I would [. . . something about air flow . . .].

They both will be water cooled but not overclocked at this moment

 

[azzazel_99]

I thought you were asking how you should setup your cards and what not. Let me try and explain what I was saying. The reference 780ti sc you have pulls cool air from inside the case and blows it out the back of the card. The acx 780ti sc you have pulls cool air from inside the case and exhausts it back into your case thus resulting in hot air being put back into your case. If you put the reference card in the top slot on your motherboard and the acx on the bottom pcie slot on your motherboard the top card (reference cooler) will be sucking in the hot air the bottom card (acx cooler) is exhausting upward towards the reference cooled 780ti which will result in your top card getting a lot hotter than normal. Performance and temperature wise you should mount the acx cooled 780ti above the referenced cooled 780ti that way you aren't blowing hot gpu exhaust air right onto the reference cooled 780ti. That make sense? Also plug your monitor into the top card not the bottom.

 

[azzazel_99]

See I have 2 acx cooled 780ti classified's so I'm doomed either way. My bottom card blows all its hot air right into the intake of my top card so my top card almost always runs hotter because it's intaking hotter air and trying to cool the gpu and vram down. The bottom card is getting the nice cool air from the bottom side of my case so it runs cooler.

 

[Rick Kraster]

Faster cards will automatically underclock to the slower card unless you overclock the slower card to match the faster one (or both to an identically higher speed).

thanks this is what i wanted to know. should have made it more clear judging the reactions