Better Case Fans

[mjohnson24]

I currently have a HAF932 amd advanced case. I have a 200mm on front and side door. i can do upto 230. They are i think 110cfms or so. I can do either a 230mm at 156cfms or i can do 4 120mm corsair AF120s at 56cfms per fan. Im wanting to see what would be best to get more air flow on my two evga gtx 1080 ftw gaming acx3.0 cards im running in SLI. One 1080 was only doing roughly 55c temperature when playing battlefield 1 but now that i have two cards one is running around the same but the other is between 72-82c which is much higher. The cards have 1 slot between them meaning if i wanted to i can add a small pciex card between them and no big deal so its not covered. Im using Slot 1 and slot 4 on the motherboard for the PCIex slots on it so the top card covers slot 2 and second card goes in slot 4 so slot 3 is accessible.

Whats yalls thoughts on more airflow? at some point i will be getting either the Phanteks Enthoo Primo case or the Thermaltake W100 or WP100 case. LEaning toward the Thermaltake. And then once i get the money ill end up doing custom watercooling probably for all of it.

[xeromist]

Most likely higher CFM won't fix it. Most cases really only need a couple of fans to be effective and it's other issues that cause heat buildup.

You didn't say which card is the hotter one but it sounds like either the new card has a badly seated heat sink or there is a dead zone around the hotter card. One thing you can try doing is swapping the two cards. Sometimes the primary card runs hotter since it has more load so swapping them will help narrow things down. If it's a dead spot you may be able to rectify that by either adding or removing slot and bay covers, or reversing the direction of fans.

Also note that while those temps are high, they are within spec. So cooler is better but unless the card is throttling you should be OK.

[mjohnson24]

xeromist wrote:
Most likely higher CFM won't fix it. Most cases really only need a couple of fans to be effective and it's other issues that cause heat buildup.

You didn't say which card is the hotter one but it sounds like either the new card has a badly seated heat sink or there is a dead zone around the hotter card. One thing you can try doing is swapping the two cards. Sometimes the primary card runs hotter since it has more load so swapping them will help narrow things down. If it's a dead spot you may be able to rectify that by either adding or removing slot and bay covers, or reversing the direction of fans.

Also note that while those temps are high, they are within spec. So cooler is better but unless the card is throttling you should be OK.

Well i will definitely try swapping the cards around and seeing what it does. I know in the EVGA PrecisionX software the one labeled GPU1 i found was the new card in slot 4 of my Mobo and GPU2 is the older 1080 thats in slot 1 of my mobo (weird thats the order it did but ), but i cant remember which one was hotter. Ill check that and find out before i swap.

My only concern is the fan speed spinning at like 2500-2800rpm's and being loud is all.

Now i do know hte card in slot one which is the orginial and first card i put in before i got the second one is the card for sure that doesnt have the thermalpads on it. That one was one of the ones they didnt put thermalpads on in the original get go but i do have thermalpads to put on it and Gelid thermal paste to use for the heatsink again.

[Korth]

Your HAF case has fairly clean front-to-back airflow. But the two GPU cards (with their two pairs of ACX3.0 fans) disrupt airflow. Your PSU fan might or might not also disrupt airflow.

Remember that reference high-end GPU cards typically use a (NVTTM-style) cooler with a blower fan designed to move a lot of air from the front of the card to to the rear slots (where almost all of the hot air is exhausted out of the chassis). But nonreference GPU cards often reengineer some sort of "improved" GPU cooler system - which invariably involves more fans ramming more air onto the card, they do indeed often run cooler (in isolation) than their boring reference counterparts, but only a fraction of the heat is exhausted out the rear of the chassis and a lot of the heat ends up spilling around the edges of the card onto the motherboard and the rest of the system. They're designed to sell leet GPU card cooling dominance, they're not really designed for optimal multi-GPU installations, all those fans just trap hot air in a dead or recirculating zone where the hot air has nowhere to go except maybe flowing across the cards again and again. It'll work, but it's counter-efficient and overall temps around one or both GPU cards tend to idle higher and throttle lower, ramping up the fans with more and more speed does force a little bit more hot air to be expelled (along an ever-diminishing curve) at the cost of much noise output (along an ever-increasing curve). There's good reason why blower-style "reference" coolers are the only approach in server racks populated with blade upon blade of densely-packed multi-GPU madness. Your HAF case helps a lot, changing to another case could make things better or could make things much worse.

Liquid-cooling your GPU cards would vastly improve specific and overall thermal performances. Plus you wouldn't need that huge side-intake fan, it's a "quiet" model but it's also placed where the operator will hear it most. A portion of the air it sucks into the chassis gets sucked up (and exhausted by) the GPU card fans, but a portion of it works against the airflow generated by the front-intake chassis fan. You could get better airflow efficiency (and less noise) by installing an internal fan or a slot cooler under your bottom GPU card, something that sucks air from inside the case and blows it towards the GPU cards. Akust sells a variety of internal cooler/mounting kits, I've been impressed by this AzenX Blitztorm System Slot Cooler before, and I've tried many kinds of PC fans over many years but I keep going back to Noctua Industrials.

Alternately, you could fashion some sort of cylinder to directly duct airflow from the chassis side fan to the GPU card "intake" surfaces. I've seen everything ranging from "ghetto" duct-tape-and-soda-bottle to "gaming" products (like those sold by Akust) to DIY precision-machined metal enclosures.