High temps for EVGA GTX 780ti SC ACX in SLI

[Halpers]

I recently added a second 780ti to my setup after getting a 1440p monitor. Previously my single 780ti would be at around 65-70 degrees under load. After adding a second video card the original one (top) would get temps of 75-80 degrees under load and the new one (bottom) would be at around 70.

I realize that in SLI config the top card will always run hotter but the temp jump concerns me. Even idle temp went up from like 30 degrees to 44. When playing higher end games like thief that keep both GPUs at 100% I have to manually bump fan speed to 70-75% to keep the top card at 80 degrees or less. Is this normal? Is there anything I can do to lower the temperature of the top card other than liquid cooling?

Here is my current setup:
Cooler Master HAF X case with 200mm side and front fans for intake and 2x 200mm top fans and a 140mm rear fan for out.
i7-4770k
noctua NH-D14 cooler
asus hero vi motherboard
16gb of ddr3 1600 gskill ripjaw
256gb ssd
2x 1tb HDDs in raid1
EVGA GTX 780ti SC ACX in SLI
850 watt evga psu

Nothing is overclocked right now and all the wires inside the case are neat/hidden to maximize airflow. Fans are all running at max rpm. Any thoughts/ideas are welcome.

 

[iAboodz]

It's probably because it doesnt get enough air into the fan, are the two gpus close to each other ?

 

[ferwindjacks]

Im betting you're cards are next to each other, meaning there is no slot in between to allow "breathing" room. Even if there is a gap, just hear this out.

You're first (top) card is inhaling the air that the 2nd (bottom) GPU is heating up. Not much to do besides water cooling and repositioning fan setup, so its something you gotta live with.

Also, you could beef up the GPU fan speed using one of EVGA nifty software tools, but that will make your computer louder (obviously). It will help with temps though.

Another way to cool the things down is to buy a higher RPM side fan (since HAF X side panel blows right on GPUs). That could bring you down a bit.

Higher temps is just what you might have to deal with. Dipping the whole thing in liquid nitrogen would probably be your best bet to get temps to acceptable levels.

 

[Halpers]

It's probably because it doesnt get enough air into the fan, are the two gpus close to each other ?

The cards have a slot between them so they are not right next to each other. I've been told elsewhere to try switching side fan to exhaust instead of intake to see if that helps and I might also try re-applying the thermal paste on the top card.

For side panel for HAF X it seems like coolermaster megaflow 200m fan is one of the best/top rated ones. If someone has a better option let me know. Noise isn't an issue for me as long as it moves a lot of air without sounding like a vacuum cleaner.

 

[ferwindjacks]

Then try adjusting GPU fan speed. Like I said, not much more than tossing on water blocks.

 

[17seconds]

People need to understand how Turbo Boost 2.0 works. It is based on a Temp Limit, another word for the target temperature that your cards are set to seek out and maintain. That temperature on a GTX 780 Ti just happens to be 82c. Note, this is not the temperature threshold, 95c, the point at which you risk damaging your GPU.

You can check your Temp Limit in PrecisionX or Afterburner. It is a key part to understanding how your card reacts to heat and which temperature your card is designed to target as a normal operating temperature. With a single ACX card, you are able to run comfortably below your Temp Limit, which promotes maximum Turbo Boost clocks and low fan speeds. When you add a second card, you increase your card's heat level, but get this, you'll NEVER go above 82-85c under normal operating conditions. Your card will increase its fan speeds and decrease its Turbo Boost clocks to maintain that 82c Temp Limit.

So, your question about your GPU temp of 80c is missing the point. That's within your card's preset target temperature, so really there's no problem there. What I think you mean to question is whether your performance is being held back by lower Turbo Boost clocks and/or are your fans being forced to work too hard, thus producing more noise than desired. You mentioned needing to increase your fan speeds to 75%, that's probably what your fans would be doing in Auto mode anyway, maybe less.

You need to give more info on your Turbo Boost clocks versus your Auto fan speeds to get a good idea of what's going on. A lot of people get alarmed when they see 80c on their card, but that's how it was designed. You've been spoiled by excellent temps on an ACX cooler with a single card, but really your temperatures are completely normal for a SLI setup. If you want to increase your Turbo Boost clocks, then I would recommend adding another fan as others have mentioned, or wait until autumn really starts to cool off your ambient air temps. But 80c in and of itself in completely normal and nothing to worry about.

 

[iAboodz]

It's still really an airflow issue, re applying paste won't give you anything. As 17seconds said you are still at safe temps. If you want to make your temps lower than that you have to do a fan curve where you choose your gpu fan speed depending on the temp.

Here is how:
http://www.overclock.net/t/1265110/the-gtx-670-overclocking-master-guide

Ignore everything just use the fan curve and adjust it as you please