Overclock.net › Forums › Cooling › Water Cooling › How much does cfm matter in cooling?
New Posts  All Forums:Forum Nav:

How much does cfm matter in cooling? - Page 2

post #11 of 19
Yep, Panaflo medium is awesome. No tick undervolted and pretty quiet at full speed. They are perfect unless you need more than 85CFM for whatever reason.
    
CPUMotherboardGraphicsRAM
955 C3 3.8ghz GA-MA790X-UD4P Sapphire HD 4830 Samsung 2 x 4GB 
Hard DriveHard DriveOptical DriveCooling
SanDisk SSD Samsung F3 Sony DVD Burner S1283/Panaflo M1 
OSMonitorPowerCase
Windows 7 22" AOC 1920x1080 Corsair CX400 Antec 300 
  hide details  
Reply
    
CPUMotherboardGraphicsRAM
955 C3 3.8ghz GA-MA790X-UD4P Sapphire HD 4830 Samsung 2 x 4GB 
Hard DriveHard DriveOptical DriveCooling
SanDisk SSD Samsung F3 Sony DVD Burner S1283/Panaflo M1 
OSMonitorPowerCase
Windows 7 22" AOC 1920x1080 Corsair CX400 Antec 300 
  hide details  
Reply
post #12 of 19
CFM means nothing on heatsinks and rads... its static pressure u want to look at

and yes thats really how loud those 3k fans are
Silent Dominator
(28 items)
 
Classy Lady
(26 items)
 
TUF Inside
(18 items)
 
  hide details  
Reply
Silent Dominator
(28 items)
 
Classy Lady
(26 items)
 
TUF Inside
(18 items)
 
  hide details  
Reply
post #13 of 19
Quote:
Originally Posted by Blindrage606 View Post
Also, I faintly remember from modern physics(overpriced hard as hell course), that once CFM-vector velocities are so great, atmosphere(liquid nature of air as a volume) will lose its capacity to lose/gain heat through convection. But thats not an issue unless you're an F18 engineer for Lockheed Martin...
That's correct, higher CFM will induce higher kinetic energy on the air particles which will absorb energy by collision with the surface of the radiator. There's a compromise by how hard you bang the air particles on to the radiator and how many of them you put through the radiator per unit of time. Static pressure is good to ensure a more or less constant flow of air particles on to the radiator ensuring continuous heat conduction.
    
CPUMotherboardGraphicsRAM
Intel Core i7-5820K Haswell-E Asus ROG Rampage V Extreme Intel X99 EVGA GeForce GTX 1080 FTW Corsair Vengeance Red LED 32GB (4x8GB) DDR4-300... 
Hard DriveHard DriveHard DriveCooling
Samsung 840 500GB SSD (SATA-6Gbps) Western Digital Black 1TB 64MB Cache HDD (SATA-... Western Digital Black 4TB 64MB Cache HDD (SATA-... NZXT Kraken X52 & 2x Corsair SP120 RGB 120mm Fa... 
CoolingCoolingCoolingOS
EVGA ACX 3.0 (Graphics Card) 4x Corsair SP120 RGB 120mm Case Fans IC Diamond 7 Carat Thermal Compound Microsoft Windows 10 Home 
MonitorKeyboardPowerCase
LG Flatron 34UM95-P 34" 3440x1440 21:9 IPS SteelSeries Apex 350 Low Profile RGB EVGA SuperNova G2 1000W Modular Corsair Crystal 570X RGB 
MouseMouse PadAudioAudio
Logitech G502 Proteus Core ModMyMachine SlamePad Aluminium Magnum Champagne Creative Labs Sound Blaster ZxR 2x Acoustic Energy Aego M 2.1 Speakers & 1 Cent... 
AudioOtherOtherOther
Beyerdynamic DT770 Pro 250Ohm Headphones (Dynam... Saitek X-55 Rhino HOTAS Logitech G27 Racing Steering Wheel HTC Vive 
  hide details  
Reply
    
CPUMotherboardGraphicsRAM
Intel Core i7-5820K Haswell-E Asus ROG Rampage V Extreme Intel X99 EVGA GeForce GTX 1080 FTW Corsair Vengeance Red LED 32GB (4x8GB) DDR4-300... 
Hard DriveHard DriveHard DriveCooling
Samsung 840 500GB SSD (SATA-6Gbps) Western Digital Black 1TB 64MB Cache HDD (SATA-... Western Digital Black 4TB 64MB Cache HDD (SATA-... NZXT Kraken X52 & 2x Corsair SP120 RGB 120mm Fa... 
CoolingCoolingCoolingOS
EVGA ACX 3.0 (Graphics Card) 4x Corsair SP120 RGB 120mm Case Fans IC Diamond 7 Carat Thermal Compound Microsoft Windows 10 Home 
MonitorKeyboardPowerCase
LG Flatron 34UM95-P 34" 3440x1440 21:9 IPS SteelSeries Apex 350 Low Profile RGB EVGA SuperNova G2 1000W Modular Corsair Crystal 570X RGB 
MouseMouse PadAudioAudio
Logitech G502 Proteus Core ModMyMachine SlamePad Aluminium Magnum Champagne Creative Labs Sound Blaster ZxR 2x Acoustic Energy Aego M 2.1 Speakers & 1 Cent... 
AudioOtherOtherOther
Beyerdynamic DT770 Pro 250Ohm Headphones (Dynam... Saitek X-55 Rhino HOTAS Logitech G27 Racing Steering Wheel HTC Vive 
  hide details  
Reply
post #14 of 19
Quote:
Originally Posted by Blindrage606 View Post
Not exactly, but in a more practical application, yes...

Static pressure is also a topic to be mentioned, a fan with higher CFM rating vs lower SP(these concepts are inversely related) will be able to push greater amounts of air as long objects are not restricting its FOV. Finding a correct equilibrium is important for choosing fans, especially for watercooled setups.

Also, I faintly remember from modern physics(overpriced hard as hell course), that once CFM-vector velocities are so great, atmosphere(liquid nature of air as a volume) will lose its capacity to lose/gain heat through convection. But thats not an issue unless you're an F18 engineer for Lockheed Martin...


EDIT: Go Kazes w/ a fan controller, stock molex is @5V. Ultimate airflow w/ control LOL
This is what I came to post, static pressure is a concern with water cooling because you need to efficiently get the air through the radiator lol.
Test
(10 items)
 
  
CPUMotherboardGraphicsRAM
i7 3820 x79-UD3 EVGA GTX 670 Samsung 1.35v low pro 
Hard DriveMonitorKeyboardPower
Crucial M4 Yamakasi Catleap Ducky DK-1087 ST-1000G 
CaseMouse
Lian Li A71F Steelseries - Ikari 
  hide details  
Reply
Test
(10 items)
 
  
CPUMotherboardGraphicsRAM
i7 3820 x79-UD3 EVGA GTX 670 Samsung 1.35v low pro 
Hard DriveMonitorKeyboardPower
Crucial M4 Yamakasi Catleap Ducky DK-1087 ST-1000G 
CaseMouse
Lian Li A71F Steelseries - Ikari 
  hide details  
Reply
post #15 of 19
As you might have discovered - its pretty basic.

The biggere amount of CFM = The bigger amount of air can be moved.

So .. Personally I try to find the best fan, with higest CFM, and lowest decibel
Main PC
(13 items)
 
  
CPUMotherboardGraphicsRAM
Core i5 760 2.8GHz @ 4.0GHz Asus P7P55D 2x Sapphire HD 5770 in CF 8GB (4x2GB) Corsair XMS3 
Hard DriveOptical DriveOSMonitor
1TB WD - Next: SSD LiteOn DVD Burner Microsoft Windows 7 Ultimate x64 3x HP S2031a 
KeyboardPowerCaseMouse
Logitech G11 Corsair TX650 Chieftec Bravo 2x Logitech MX1000 (No flat battery) 
Mouse Pad
Icemat v2 
  hide details  
Reply
Main PC
(13 items)
 
  
CPUMotherboardGraphicsRAM
Core i5 760 2.8GHz @ 4.0GHz Asus P7P55D 2x Sapphire HD 5770 in CF 8GB (4x2GB) Corsair XMS3 
Hard DriveOptical DriveOSMonitor
1TB WD - Next: SSD LiteOn DVD Burner Microsoft Windows 7 Ultimate x64 3x HP S2031a 
KeyboardPowerCaseMouse
Logitech G11 Corsair TX650 Chieftec Bravo 2x Logitech MX1000 (No flat battery) 
Mouse Pad
Icemat v2 
  hide details  
Reply
post #16 of 19
Static pressure is just one point on th PQ curve where restriction is absolute and flow is zero. Max CFM is the opposite extreme where restriction is zero.

A fan installed on a radiator is operating between these two points, so technically they are both equally important. Unfortunately the points themselves don't tell you about the PQ path in between which is not linear.

In the end, neither one is a very good indicator of performance on a radiator.

To make matters worse, noise ratings are often tested differently and mathematically derived leaving you with an apples to oranges noise problem. Make it even worse by the fact that dbA is basically a frequency weighted pressure indicator that is designed to indicate damage not annoyance. Motor ticks and buzzing and harmonics that fluctuate and cause very annoying noises can measure equally or better than a constant smooth tone that is less irritating.

Bottom line, don't trust any box specs...they are extremely poor indicators of performance and noise annoyance especially the noise pieces...they may as well not even be in print...especially the dbA ratings....useless numbers and not to be trusted as indicators of the real world.

CFM is probably worthwhile in an open case fan condition, but even with that you have restriction in the case.
Edited by Martinm210 - 4/23/11 at 3:53pm
    
CPUMotherboardGraphicsRAM
3930K ASrock X79 Ext7 Evga GTX570 CORSAIR Vengeance 16GB 
Hard DriveOptical DriveOSMonitor
Phoenix SSD+2TB Seagate drives ASUS DVD-RW combo Windows 7 28" Hanns-G HZ281 
KeyboardPowerCaseMouse
MS Natural Corsair TX650 Danger Den Torture Rack Logitech MX518 
Mouse Pad
Desk 
  hide details  
Reply
    
CPUMotherboardGraphicsRAM
3930K ASrock X79 Ext7 Evga GTX570 CORSAIR Vengeance 16GB 
Hard DriveOptical DriveOSMonitor
Phoenix SSD+2TB Seagate drives ASUS DVD-RW combo Windows 7 28" Hanns-G HZ281 
KeyboardPowerCaseMouse
MS Natural Corsair TX650 Danger Den Torture Rack Logitech MX518 
Mouse Pad
Desk 
  hide details  
Reply
post #17 of 19
Quote:
Originally Posted by FreakaZoidDK View Post
As you might have discovered - its pretty basic.

The biggere amount of CFM = The bigger amount of air can be moved.

So .. Personally I try to find the best fan, with higest CFM, and lowest decibel
High CFM doesn't necessarily equate to better performance pushing air through a radiator...high Static Pressure is necessary in order to ensure that the air is actually making it through the radiator fins (especially closely packed fins on thinner rads).

This is why a lower CFM (57) Gentle Typhoon AP15 can perform better on a rad than a higher CFM (70) Yate Loon Medium.

Check out martinm210's tests.

*edit* lol, of course Martin posts in here right before I do...
Edited by whiteslashasian - 4/23/11 at 4:47pm
    
CPUMotherboardGraphicsRAM
Intel Core i5 2500k GIGABYTE GA-Z68XP-UD4 Sapphire HD 6950 2GB Mushkin Enhanced Blackline 8GB 1600 
Hard DriveHard DriveOptical DriveOS
ADATA S599 Samsung Spinpoint T NEC DVD-RW W7 
MonitorMonitorPowerCase
Dell 2007wfp Dell 2007wfp 1000w Ultra X3 Lian Li PC-V2000b Plus II 
  hide details  
Reply
    
CPUMotherboardGraphicsRAM
Intel Core i5 2500k GIGABYTE GA-Z68XP-UD4 Sapphire HD 6950 2GB Mushkin Enhanced Blackline 8GB 1600 
Hard DriveHard DriveOptical DriveOS
ADATA S599 Samsung Spinpoint T NEC DVD-RW W7 
MonitorMonitorPowerCase
Dell 2007wfp Dell 2007wfp 1000w Ultra X3 Lian Li PC-V2000b Plus II 
  hide details  
Reply
post #18 of 19
Static pressure for push, high cfm for exhaust
post #19 of 19
As for noise, you're not going to run them at maximum anyway...

Get a fan controller -> Scythe Kaze Master Pro
THE PHOENIX
(20 items)
 
  
CPUMotherboardGraphicsRAM
Intel Core i5-4690K/4.5GHz GA-Z97X-UD5H-BK EVGA GTX760 2GB SC/ACX  G.Skill Trident X 2400/16GB  
Hard DriveHard DriveHard DriveHard Drive
Samsung 850 EVO 120GB PNY CS1311 120GB Crucial M4 64GB WD VelociRaptor 150GB 
Hard DriveOptical DriveCoolingOS
WDC Black 1TB ASUS Thermalright Silver Arrow IB-E Extreme Linux Mint 18.1 Cinnamon/64 
OSOSMonitorKeyboard
Windows10 Pro/64 Ubuntu 16.04 ASUS MX259H 25" Frameless Corsair K70 
PowerCaseMouseAudio
Antec TP-New 750W  Phanteks Enthoo Luxe Tempered Glass Logitech ASUS Xonar D1 
  hide details  
Reply
THE PHOENIX
(20 items)
 
  
CPUMotherboardGraphicsRAM
Intel Core i5-4690K/4.5GHz GA-Z97X-UD5H-BK EVGA GTX760 2GB SC/ACX  G.Skill Trident X 2400/16GB  
Hard DriveHard DriveHard DriveHard Drive
Samsung 850 EVO 120GB PNY CS1311 120GB Crucial M4 64GB WD VelociRaptor 150GB 
Hard DriveOptical DriveCoolingOS
WDC Black 1TB ASUS Thermalright Silver Arrow IB-E Extreme Linux Mint 18.1 Cinnamon/64 
OSOSMonitorKeyboard
Windows10 Pro/64 Ubuntu 16.04 ASUS MX259H 25" Frameless Corsair K70 
PowerCaseMouseAudio
Antec TP-New 750W  Phanteks Enthoo Luxe Tempered Glass Logitech ASUS Xonar D1 
  hide details  
Reply
New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: Water Cooling
Overclock.net › Forums › Cooling › Water Cooling › How much does cfm matter in cooling?