The Corsair User Forums  

Go Back   The Corsair User Forums > Corsair Product Discussion > Cooling

Reply
 
Thread Tools Search this Thread Rate Thread Display Modes
  #1  
Old 04-09-2016, 04:03 PM
Slask Slask is offline
Registered User
Slask's PC Specs
 
Join Date: Apr 2016
Posts: 3
POST ID # = 846413
Slask Reputation: 10
Default H75 "optimal" pump RPM?

Ohoy! I'm a bit of a water cooling noob.

I recentely installed an H75 liquid cooler and I'm trying to make sure it's running at its optimal settings.
I've seen people saying you should disable the automatic speed for the pump in the BIOS, since disabling it will cause it to run at 100%.
Doing so puts it at around 1450 RPM when I'm in the BIOS, but any and all fan speed monitoring software tells me it's doing around 1100-1200 RPM at full load. The radiator fans rarely go over 1000 RPM either. Perhaps it's normal, since the CPU temp is at around 40 celcius when gaming.

What's the experience of any other H75 owners? And any idea why the BIOS and other software show such different numbers?

Last edited by Slask; 04-09-2016 at 04:10 PM.
Reply With Quote


  #2  
Old 04-09-2016, 05:57 PM
c-attack c-attack is offline
Registered User
c-attack's PC Specs
 
Join Date: Jun 2014
Posts: 9,247
POST ID # = 846429
c-attack c-attack Reputation: 107
Default

Max pump speed is 1450 rpm +- 50 and you should run it at 100%. Undervolting the pump will shorten its lifespan. However, the unit will still be effective at a reduced pump speed, since short run systems aren't as dependent upon flow rate.

I see Asus motherboard. Are you running AI Suite or any other software fan control? What program is reporting the 1100-1200 number?

Radiator fan speed will be dependent on whatever is giving them directions. Something is set for in the BIOS. If you never hit more than 40-50C on the CPU cores, then 1000 rpm is just fine. Most of the time you don't want the radiator fans to run any faster than necessary. However, if you mounted it as rear exhaust, sometimes it is beneficial to deliberately set them to a higher speed to air in GPU waste heat exhaust.
Reply With Quote


  #3  
Old 04-09-2016, 06:29 PM
Slask Slask is offline
Registered User
Slask's PC Specs
 
Join Date: Apr 2016
Posts: 3
POST ID # = 846432
Slask Reputation: 10
Default

Thanks for some clarification!

Indeed, that was what I was trying to do. I disabled Q-Fan for the pump fan to make it run at full speed. After some testing I figured out that the RPM was at 100% (~1450) in the BIOS, but OpenHardwareMonitor and AI Suite Thermal Radar was showing less because AI is overriding the settings in the BIOS with its own fan curve. After altering that curve myself the pump now runs at a nice 100%.

Though I thought the BIOS had priority over AI Suite.

Ramping up the radiator fan speeds might not be a terrible idea, as it is now the GPU fans are pointing down toward the PSU, where there's not much airflow going on, as a result it's at about 50°C at idle.

Last edited by Slask; 04-09-2016 at 06:33 PM.
Reply With Quote


  #4  
Old 04-09-2016, 07:51 PM
c-attack c-attack is offline
Registered User
c-attack's PC Specs
 
Join Date: Jun 2014
Posts: 9,247
POST ID # = 846441
c-attack c-attack Reputation: 107
Default

It is a bit of a complex relationship between the BIOS and AI Suite. For fan control, the BIOS settings will prevail during boot until the desktop loads and the AI suite program kicks in. However, the PWM/DC setting will override anything AI suite wants to do. It is even more complicated if you try and use AI suite for overclocking. Works OK when BIOS is at default and then run the tuner, but making subsequent changes is always tricky.

What is 50C at idle? Hopefully you mean the 970. If so, don't sweat it. That is about the standard idle operating temperature for most of the 970 variations, particularly if you are using the zero fan settings on these cards. If you really want to take a bite out of your GPU temps, use MSI afterburner/EVGA precision, etc. to take control of the GPU fan profile. Only the GPU's own fans can really cool the board hidden away in the casing. Even an inaudible 15 or 20% duty cycle will knock 10C off your GPU temps and eliminate the fan rush that kicks in when you blow by 70C in "zero" mode. I have two stacked and with a nothing more than 40% fan under load, my GPU's won't go past 61-63C with a +150 MHz overclock.
Reply With Quote


  #5  
Old 04-10-2016, 04:52 AM
Slask Slask is offline
Registered User
Slask's PC Specs
 
Join Date: Apr 2016
Posts: 3
POST ID # = 846489
Slask Reputation: 10
Default

I see. Since I'm running the Z77 which is a bit old now I don't seem to have access to any PWM/DC settings found in the newer cards. All I have is the Q-Fan control.

Hehe, yes, the 970. Although its temp (and noise) will usually drop to around 40-45 after running a game for a while. The 970 is by far the thing making the most noise when initially running a game. But that's probably just because I'm running the default fan settings.
Reply With Quote


  #6  
Old 04-10-2016, 09:20 AM
c-attack c-attack is offline
Registered User
c-attack's PC Specs
 
Join Date: Jun 2014
Posts: 9,247
POST ID # = 846513
c-attack c-attack Reputation: 107
Default

You're right, the dual PWM/DC headers really didn't come in until Z97 that option probably is not present in AI Suite 2, but I wasn't sure about the CPU/OPT headers.

Definitely look into manual control over the fans. You don't have to overclock the card. You can use Afterburner/Precision for fan control only. With 2x970, I only made it a day or two before I had to stop the fan surging every time the temps went past 70C. Just a little fan speed will keep things much cooler on a more permanent basis.
Reply With Quote


Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 05:13 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2019, vBulletin Solutions, Inc.