Page 1 of 2 12 LastLast
Results 1 to 16 of 19

Thread: CPU heatsink fan - suck or blow?

  1. #1
    Taz
    Taz is offline
    Senior Member Taz's Avatar
    Join Date
    Jan 2005
    Location
    London
    Posts
    2,152
    Thanks
    57
    Thanked
    29 times in 27 posts
    • Taz's system
      • Motherboard:
      • Gigabyte Z270 HD3P
      • CPU:
      • Intel Core i5 7600K
      • Memory:
      • Corsair CMK16GX4M2B3200C16R Vengeance LPX 16 GB
      • Storage:
      • Samsung 960 EVO M.2-2280 500GB (PCIe) + 1TB Sandisk Ultra II SSD (SATA)
      • Graphics card(s):
      • Asus NVIDIA GeForce GTX 1070 OC
      • PSU:
      • Corsair CS550M 550W Hybrid
      • Case:
      • NZXT Source 340
      • Operating System:
      • Windows 10 Pro
      • Monitor(s):
      • 34" Asus Designo Curve MX34VQ UWQHD Monitor
      • Internet:
      • Virgin Media M350

    CPU heatsink fan - suck or blow?

    I'm going to fit a 92mm fan onto my XP-90 heatsink shortly and I'm not sure whether there's a 'proper' orientation that should be used? Should the fan suck the hot air from the CPU and blow it out upwards or should it blow cooler air down into the CPU? Or doesn't it matter?

  2. #2
    Real Ultimate Power! Grey M@a's Avatar
    Join Date
    Oct 2003
    Location
    Newcastle
    Posts
    4,625
    Thanks
    52
    Thanked
    156 times in 139 posts
    • Grey M@a's system
      • Motherboard:
      • Gigabyte Z97X Gaming 7
      • CPU:
      • i7 4790K (With H100i cooling)
      • Memory:
      • Corsair Vengeance Pro 16GB DDR3 (2 x 8GB)
      • Storage:
      • Samsung 840 Pro 128GB SSD, 1TB Cavier Black WD HD, 4TB Cavier Black WD HD
      • Graphics card(s):
      • MSI R9 390X Gaming Edition 8GB
      • PSU:
      • SuperFlower Leadex GOLD 850W Fully Modular
      • Case:
      • Corsair 650D
      • Operating System:
      • Windows 8.1 Pro x64
      • Monitor(s):
      • 24" LG 24GM77-B 144Hz
      • Internet:
      • 100MB Virgin Media Cable
    I have that sink and it's definately a blow orientation otherwise the heatpipes wot do their job

  3. #3
    Taz
    Taz is offline
    Senior Member Taz's Avatar
    Join Date
    Jan 2005
    Location
    London
    Posts
    2,152
    Thanks
    57
    Thanked
    29 times in 27 posts
    • Taz's system
      • Motherboard:
      • Gigabyte Z270 HD3P
      • CPU:
      • Intel Core i5 7600K
      • Memory:
      • Corsair CMK16GX4M2B3200C16R Vengeance LPX 16 GB
      • Storage:
      • Samsung 960 EVO M.2-2280 500GB (PCIe) + 1TB Sandisk Ultra II SSD (SATA)
      • Graphics card(s):
      • Asus NVIDIA GeForce GTX 1070 OC
      • PSU:
      • Corsair CS550M 550W Hybrid
      • Case:
      • NZXT Source 340
      • Operating System:
      • Windows 10 Pro
      • Monitor(s):
      • 34" Asus Designo Curve MX34VQ UWQHD Monitor
      • Internet:
      • Virgin Media M350
    Quote Originally Posted by Grey M@a
    I have that sink and it's definately a blow orientation otherwise the heatpipes wot do their job
    Cheers, mate. The reason I asked what may have appeared to be a daft question is the following page from an excellent review:

    http://www.silentpcreview.com/article194-page2.html

    Quote: "Thermalright assures us that cooling is the same with the fan blowing up or down"

    I have two 120mm fans in my case and if I mounted the HS fan so that it sucked air then the hot air would enter the airstream of the two main case fans.

  4. #4
    Now with added sobriety Rave's Avatar
    Join Date
    Jul 2003
    Location
    SE London
    Posts
    9,948
    Thanks
    501
    Thanked
    399 times in 255 posts
    Experiment then. Put it on blow, load up the processor with Prime95 and then take the temp after 15-20 minutes. Then set it to suck and do the same. Go with whatever works best. My money's on blow though.

  5. #5
    Taz
    Taz is offline
    Senior Member Taz's Avatar
    Join Date
    Jan 2005
    Location
    London
    Posts
    2,152
    Thanks
    57
    Thanked
    29 times in 27 posts
    • Taz's system
      • Motherboard:
      • Gigabyte Z270 HD3P
      • CPU:
      • Intel Core i5 7600K
      • Memory:
      • Corsair CMK16GX4M2B3200C16R Vengeance LPX 16 GB
      • Storage:
      • Samsung 960 EVO M.2-2280 500GB (PCIe) + 1TB Sandisk Ultra II SSD (SATA)
      • Graphics card(s):
      • Asus NVIDIA GeForce GTX 1070 OC
      • PSU:
      • Corsair CS550M 550W Hybrid
      • Case:
      • NZXT Source 340
      • Operating System:
      • Windows 10 Pro
      • Monitor(s):
      • 34" Asus Designo Curve MX34VQ UWQHD Monitor
      • Internet:
      • Virgin Media M350
    You're right Rave (as usual!). If you look at the review (link in one of my posts above) - the third page of that review shows temperature readings with both orientations. The fan blowing down on the CPU produces slightly lower temperatures, which I guess makes sense.

  6. #6
    Now with added sobriety Rave's Avatar
    Join Date
    Jul 2003
    Location
    SE London
    Posts
    9,948
    Thanks
    501
    Thanked
    399 times in 255 posts
    It still might be worth experimenting though since it'll take all of two minutes. You never know whether an airflow idiosyncracy in your case might swing the balance- it seems their testing is done on a bare testbench. Either way I suspect there won't be much in it.

  7. #7
    Member
    Join Date
    May 2004
    Posts
    146
    Thanks
    1
    Thanked
    2 times in 1 post
    noob question how do u change the fan
    from suck to blow?

  8. #8
    Senior Member chriswood_7's Avatar
    Join Date
    Jan 2005
    Location
    Gateshead
    Posts
    1,485
    Thanks
    2
    Thanked
    7 times in 6 posts
    • chriswood_7's system
      • Motherboard:
      • Asus M2NE SLi
      • CPU:
      • AMD X2 5200+
      • Memory:
      • 3GB DDR2 6400
      • Storage:
      • 1x 120GB + 1x 320GB Seagate IDE
      • Graphics card(s):
      • 512MB BFG 8800GT OC2
      • PSU:
      • 680W Hiper PSU
      • Case:
      • Thermaltake Soprano w/ Window
      • Monitor(s):
      • 15" HPF50s
      • Internet:
      • 10Mbit Virgin Media
    Turn it upside down

    Unscrew it and make sure that the sticker side is facing down for a blow or for a suck sticker side up. The air always the way the sticker is facing!

    Chris

  9. #9
    Senior Member
    Join Date
    Jan 2005
    Posts
    712
    Thanks
    0
    Thanked
    1 time in 1 post
    ..."It's Mega-Maid! She's gone from suck to blow!"...
    Classic Spaceballs line...

    S.

  10. #10
    HEXUS webmaster Steve's Avatar
    Join Date
    Nov 2003
    Posts
    14,283
    Thanks
    293
    Thanked
    841 times in 476 posts
    The problem with it sucking is that there's a negative pressure in the heatsink, and the middle of the heatsink gets about zero airflow. At least with it blowing there's some pressure there, and some airflow downwards towards the middle of the heatsink, although there's still a "deadzone" because of the fan's hub.
    PHP Code:
    $s = new signature();
    $s->sarcasm()->intellect()->font('Courier New')->display(); 

  11. #11
    Senior Trouble Maker muddyfox470's Avatar
    Join Date
    Jul 2004
    Location
    moving to Suffolk
    Posts
    3,103
    Thanks
    103
    Thanked
    46 times in 39 posts
    • muddyfox470's system
      • Motherboard:
      • Abit I-N73HD
      • CPU:
      • E4500
      • Memory:
      • 4Gb PC6400 Corsair ?
      • Storage:
      • 2 x Seagate 7200.12 500Gb and 1 x Hitachi 7k1000.b 750gb
      • Graphics card(s):
      • Powercolor 4850
      • PSU:
      • Corsair HX520W
      • Case:
      • Silverstone SG-01e
      • Monitor(s):
      • Fujitsu D22W-1
      • Internet:
      • BT Home
    blow normally is best
    Mac fancier > white macbook base spec .................. CS: muddyfirebang

  12. #12
    Taz
    Taz is offline
    Senior Member Taz's Avatar
    Join Date
    Jan 2005
    Location
    London
    Posts
    2,152
    Thanks
    57
    Thanked
    29 times in 27 posts
    • Taz's system
      • Motherboard:
      • Gigabyte Z270 HD3P
      • CPU:
      • Intel Core i5 7600K
      • Memory:
      • Corsair CMK16GX4M2B3200C16R Vengeance LPX 16 GB
      • Storage:
      • Samsung 960 EVO M.2-2280 500GB (PCIe) + 1TB Sandisk Ultra II SSD (SATA)
      • Graphics card(s):
      • Asus NVIDIA GeForce GTX 1070 OC
      • PSU:
      • Corsair CS550M 550W Hybrid
      • Case:
      • NZXT Source 340
      • Operating System:
      • Windows 10 Pro
      • Monitor(s):
      • 34" Asus Designo Curve MX34VQ UWQHD Monitor
      • Internet:
      • Virgin Media M350
    Blow it is then! Thanks for all the advice.

  13. #13
    HEXUS.timelord. Zak33's Avatar
    Join Date
    Jul 2003
    Location
    I'm a Jessie
    Posts
    35,185
    Thanks
    3,126
    Thanked
    3,179 times in 1,926 posts
    • Zak33's system
      • Storage:
      • Kingston HyperX SSD, Hitachi 1Tb
      • Graphics card(s):
      • Nvidia 1050
      • PSU:
      • Coolermaster 800w
      • Case:
      • Silverstone Fortress FT01
      • Operating System:
      • Win10
      • Internet:
      • Zen FTC uber speedy
    *cough*

    subtle hint.....sometimes a fan works best if its held further from the heatsink...on little feet or spacers.

    The centre of a fan is all motor...the baldes are on the outside. There is a dead area in the centre....but at a short distance it swirls together.

    I have had 3 different heatsinks that worked better with the fan further away.

    I made thew feet with little bits of plastic....just glued them on....if they didnt work I snapped them off.

    Quote Originally Posted by Advice Trinity by Knoxville
    "The second you aren't paying attention to the tool you're using, it will take your fingers from you. It does not know sympathy." |
    "If you don't gaffer it, it will gaffer you" | "Belt and braces"

  14. #14
    Member
    Join Date
    Jan 2005
    Location
    North Carolina, US
    Posts
    73
    Thanks
    0
    Thanked
    0 times in 0 posts
    Some times with a 92mm heatsink you my want to think of funneling the air from a 120mm fan into the heatsink. That’s a great way to get more cooling for your buck, and get rid of any “deadzones” you may have otherwise. You can find a couple really great articles on the subject here.
    Tweak3D’s cooling guide
    Spode’s ducting/cooling guide
    (If I remember correctly they also has some info on why it may sometimes be better to err.. withdraw air than to.. expel air)

  15. #15
    Senior Amoeba iranu's Avatar
    Join Date
    Oct 2003
    Location
    On the dinner table. Blechh!
    Posts
    3,535
    Thanks
    111
    Thanked
    156 times in 106 posts
    • iranu's system
      • Motherboard:
      • Asus Maximus Gene VI
      • CPU:
      • 4670K @4.3Ghz
      • Memory:
      • 8Gb Samsung Green
      • Storage:
      • 1x 256Gb Samsung 830 SSD 2x640gb HGST raid 0
      • Graphics card(s):
      • MSI R9 390
      • PSU:
      • Corsair HX620W Modular
      • Case:
      • Cooler Master Silencio 352
      • Operating System:
      • Win 7 ultimate 64 bit
      • Monitor(s):
      • 23" DELL Ultrasharp U2312HM
      • Internet:
      • 16mb broadband
    Quote Originally Posted by Raggy
    Some times with a 92mm heatsink you my want to think of funneling the air from a 120mm fan into the heatsink. That’s a great way to get more cooling for your buck, and get rid of any “deadzones” you may have otherwise.
    I have a ducted 120mm fan at the rear of my case that sits right over the NB and cpu heatsink which was working as a normal rear case fan i.e. expelling hot air.

    CPU temps were @ 50°C on an overclocked 2500 @ 3200 speeds.

    I turned the fan around so it blows cold air onto the mobo and voila

    CPU temps are now 39°C idle, 43°C load.

  16. #16
    Senior Member
    Join Date
    Jul 2003
    Location
    Heidelberg
    Posts
    1,166
    Thanks
    9
    Thanked
    4 times in 4 posts
    • silentphoenix's system
      • CPU:
      • Phenom X4 945
      • Memory:
      • 2 x 4 Gb Corsair 1666 Mhz DDR3
      • Storage:
      • 80 Gb SSD + 2 Tb HDD
      • Graphics card(s):
      • PCS+ 5850
      • PSU:
      • Antec TP 650w
      • Operating System:
      • Windows 7 64 bit
      • Monitor(s):
      • BenQ FP241PW
      • Internet:
      • 12 Mb/s
    Also by blowing down you get better airflow over your mofsets (if there close to ure CPU)
    Genetically modified crops - answer to starvation in Africa?

Page 1 of 2 12 LastLast

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Does anyone know the db level of a P4 Retail Heatsink and fan?
    By subucni in forum PC Hardware and Components
    Replies: 1
    Last Post: 19-01-2005, 08:49 PM
  2. Quite fan for SP94 heatsink !
    By Alkan in forum PC Hardware and Components
    Replies: 4
    Last Post: 07-01-2005, 07:59 PM
  3. Can I replace the CPU heatsink fan?
    By YorkieBen in forum PC Hardware and Components
    Replies: 1
    Last Post: 22-11-2004, 11:10 PM
  4. CPU TIM Guide
    By Steve in forum Help! Quick Relief From Tech Headaches
    Replies: 0
    Last Post: 30-05-2004, 02:59 PM
  5. Shuttle fan - suck or blow?
    By Prodigy in forum PC Hardware and Components
    Replies: 5
    Last Post: 23-02-2004, 07:36 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •