Evan
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June 05, 2015, 09:25:03 PM |
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Max be 239CFM That's very close to my Big boy deltas I use to cool my radiator for my OC i7 3930k~ 4.7ghz..... Whats the Air Pressure? My delta at 252CFM is: 1.412 IN H2O 35.877 mmH2O
What do you mean by "1.412 IN H2O 35.877 mmH2O". I'm sure you make sense. It's just that I know the lingo. 1.412 Iches of H2O Or 35.877 milmeters H2O Often called a 'head' of water It is the pressure required to support a water column of the specified height. It is equivalent to 9.80665 Pa, using the equation: P = ρ·g·h/1000 or TL/DR how hard the air coming from that fan is pushing
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toptek
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June 05, 2015, 09:30:42 PM |
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Max be 239CFM That's very close to my Big boy deltas I use to cool my radiator for my OC i7 3930k~ 4.7ghz..... Whats the Air Pressure? My delta at 252CFM is: 1.412 IN H2O 35.877 mmH2O
What do you mean by "1.412 IN H2O 35.877 mmH2O". I'm sure you make sense. It's just that I know the lingo. I was wondering to so i looked it up . ![Smiley](https://bitcointalk.org/Smileys/default/smiley.gif) . Max. Air Pressure: 1.412 IN H2O 35.877 mmH2O mmH2O Millimeters of Water (unit of pressure) mmH2O Also found in: Encyclopedia. Acronym Definition mmH2O Millimeters of Water (unit of pressure) Copyright 1988-2014 AcronymFinder.com, All rights reserved. Various versions feature a combination of unique properties such as ultra-low weight and stretchiness, or enhanced moisture permeability and water repellency up to pressures of 10,000 mmH2O or greater achieved through special lamination. China,Japan : Nantong Teijin to Present High-performance, ... by Mena Report 5mm, the height is 11mm, and the value of the air pressure drop is 16 mmH2O, Fig. Determination of the optimal design parameters for the wavy air fins ... by Ilies, Paul; Naghi, Mihai; Mare, Ciprian; Sucila, Marius / Annals of DAAAM & Proceedings This fine denier spunbond fabric of 17 gsm reaches 100-140 mmH2O hydrostatic head, which complies with most of the market requirements for barrier leg cuffs with no melt blown layer between two spunbond layers.
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NotFuzzyWarm
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Evil beware: We have waffles!
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June 05, 2015, 10:49:39 PM |
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Max be 239CFM That's very close to my Big boy deltas I use to cool my radiator for my OC i7 3930k~ 4.7ghz..... Whats the Air Pressure? My delta at 252CFM is: 1.412 IN H2O 35.877 mmH2O
What do you mean by "1.412 IN H2O 35.877 mmH2O". I'm sure you make sense. It's just that I know the lingo. 1.412 Iches of H2O Or 35.877 milmeters H2O Often called a 'head' of water It is the pressure required to support a water column of the specified height. It is equivalent to 9.80665 Pa, using the equation: P = ρ·g·h/1000 or TL/DR how hard the air coming from that fan is pushing It refers to how much resistance the fan can overcome while moving x-amount of air. In our case, the resistance comes from pushing the air through the narrow passageways of the heatsinks. Another term for it would be back-pressure. The higher that resistance the harder the fans has to work to move air through it. Fans for miners or any other device with high-density fins on the power devices have to over come a substantial back-pressure to be able to move the required airflow through the heatsinks. By and large to produce high pressure a fan either A) has to be fairly thick to control how much air leaks between the fan blades and the housing. Is why most PC fans @ 25mm thick suck at producing any real pressure. Miner fans are generally >35mm thick. Or B) the other way to get the pressure is speed. Put the 2 together and yer Golden.
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Geiger (OP)
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June 06, 2015, 12:51:56 PM |
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Max be 239CFM That's very close to my Big boy deltas I use to cool my radiator for my OC i7 3930k~ 4.7ghz..... Whats the Air Pressure? My delta at 252CFM is: 1.412 IN H2O 35.877 mmH2O
What do you mean by "1.412 IN H2O 35.877 mmH2O". I'm sure you make sense. It's just that I know the lingo. 1.412 Iches of H2O Or 35.877 milmeters H2O Often called a 'head' of water It is the pressure required to support a water column of the specified height. It is equivalent to 9.80665 Pa, using the equation: P = ρ·g·h/1000 or TL/DR how hard the air coming from that fan is pushing It refers to how much resistance the fan can overcome while moving x-amount of air. In our case, the resistance comes from pushing the air through the narrow passageways of the heatsinks. Another term for it would be back-pressure. The higher that resistance the harder the fans has to work to move air through it. Fans for miners or any other device with high-density fins on the power devices have to over come a substantial back-pressure to be able to move the required airflow through the heatsinks. By and large to produce high pressure a fan either A) has to be fairly thick to control how much air leaks between the fan blades and the housing. Is why most PC fans @ 25mm thick suck at producing any real pressure. Miner fans are generally >35mm thick. Or B) the other way to get the pressure is speed. Put the 2 together and yer Golden. You guys seem pretty knowledgable. How would 2 fans stacked together work? Twice as good, waste of a fan or total disaster?
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Evan
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![](https://bitcointalk.org/Themes/custom1/images/post/xx.gif) |
June 06, 2015, 01:44:33 PM Last edit: June 06, 2015, 01:59:01 PM by Evan |
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Max be 239CFM That's very close to my Big boy deltas I use to cool my radiator for my OC i7 3930k~ 4.7ghz..... Whats the Air Pressure? My delta at 252CFM is: 1.412 IN H2O 35.877 mmH2O
What do you mean by "1.412 IN H2O 35.877 mmH2O". I'm sure you make sense. It's just that I know the lingo. 1.412 Iches of H2O Or 35.877 milmeters H2O Often called a 'head' of water It is the pressure required to support a water column of the specified height. It is equivalent to 9.80665 Pa, using the equation: P = ρ·g·h/1000 or TL/DR how hard the air coming from that fan is pushing It refers to how much resistance the fan can overcome while moving x-amount of air. In our case, the resistance comes from pushing the air through the narrow passageways of the heatsinks. Another term for it would be back-pressure. The higher that resistance the harder the fans has to work to move air through it. Fans for miners or any other device with high-density fins on the power devices have to over come a substantial back-pressure to be able to move the required airflow through the heatsinks. By and large to produce high pressure a fan either A) has to be fairly thick to control how much air leaks between the fan blades and the housing. Is why most PC fans @ 25mm thick suck at producing any real pressure. Miner fans are generally >35mm thick. Or B) the other way to get the pressure is speed. Put the 2 together and yer Golden. You guys seem pretty knowledgable. How would 2 fans stacked together work? Twice as good, waste of a fan or total disaster? Fan stacking is more marketing hype than a viable cooling technique, don’t think you can get twice the airflow – if you’re lucky, MAYBE an additional 20%. When stacking two fans, the theoretical max airflow will be the same, but theoretical max pressure will double. From what people are saying about how small a performance increase they get, one could guess the airflow with just one fan is closer to max airflow than to max pressure. So stacking a fan doesn’t help much. Adding a fan in parallel would more likely help, but the airflow will far from double. This is because to double the airflow through an obstacle, one must also double the pressure (so actually 4 fans are needed). https://www.youtube.com/watch?v=VUbpb23yTK8Also you'de be better off setting the case to "push/pull like this out <*#s5#*< in That way the air in and out is balanced and they are not fighting or creating areas of high or low pressure... The biggest loss in the airflow game is unbalanced airflow in & out of the case. If you put in too much air you create a high pressure zone in your case and the fan has to fight this pressure to get the air across the fins. This is why sealing the top of the case result in lower temps. I personally helped a friend using Duct tape and Plasticard build a "lid" for his S5.. it dropped for him over all 2 degrees but that was with a single fan and not the push pull as described. More important for him it made for a Quieter over all system.
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Vorta
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June 06, 2015, 10:51:47 PM |
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Vorta, did you do any fan mods?@
Yes, I have (ended up doing this). 2x Scythe Ultra Kaze (push-pull) has proven to be the best in airflow vs. sound ratio. You'll also be able to overclock your miner. Push-pull combination will always work better than any push-only configuration on the S5 because of a lot of air escaping the heatsink before reaching it's end. I would recommend not buying Deltas as they are very loud. I would also not recommend overclocking the miner while using only one fan. Unless you have an infrared thermometer to monitor the temperatures of chips in the back of the miner ensuring they don't go over 90°C as you're testing the frequencies.
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Geiger (OP)
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June 07, 2015, 01:55:36 PM |
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Vorta, did you do any fan mods?@
Yes, I have (ended up doing this). 2x Scythe Ultra Kaze (push-pull) has proven to be the best in airflow vs. sound ratio. You'll also be able to overclock your miner. Push-pull combination will always work better than any push-only configuration on the S5 because of a lot of air escaping the heatsink before reaching it's end. I would recommend not buying Deltas as they are very loud. I would also not recommend overclocking the miner while using only one fan. Unless you have an infrared thermometer to monitor the temperatures of chips in the back of the miner ensuring they don't go over 90°C as you're testing the frequencies. Sounds as though BitMain should have put the thermostat at the back of the unit because those chips get so much hotter.
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Evan
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![](https://bitcointalk.org/Themes/custom1/images/post/xx.gif) |
June 07, 2015, 02:14:49 PM |
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Vorta, did you do any fan mods?@
Yes, I have (ended up doing this). 2x Scythe Ultra Kaze (push-pull) has proven to be the best in airflow vs. sound ratio. You'll also be able to overclock your miner. Push-pull combination will always work better than any push-only configuration on the S5 because of a lot of air escaping the heatsink before reaching it's end. I would recommend not buying Deltas as they are very loud. I would also not recommend overclocking the miner while using only one fan. Unless you have an infrared thermometer to monitor the temperatures of chips in the back of the miner ensuring they don't go over 90°C as you're testing the frequencies. Sounds as though BitMain should have put the thermostat at the back of the unit because those chips get so much hotter. or smartly... run the fan from the back to the front ![Smiley](https://bitcointalk.org/Smileys/default/smiley.gif)
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I am poor, but i do work for Coin ![Smiley](https://bitcointalk.org/Smileys/default/smiley.gif) 1PtHcavXoakgNkQfEQdvnvEksEY2NvwaLM
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amelen
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![](https://bitcointalk.org/Themes/custom1/images/post/xx.gif) |
June 07, 2015, 09:55:57 PM |
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Vorta, did you do any fan mods?@
Yes, I have (ended up doing this). 2x Scythe Ultra Kaze (push-pull) has proven to be the best in airflow vs. sound ratio. You'll also be able to overclock your miner. Push-pull combination will always work better than any push-only configuration on the S5 because of a lot of air escaping the heatsink before reaching it's end. I would recommend not buying Deltas as they are very loud. I would also not recommend overclocking the miner while using only one fan. Unless you have an infrared thermometer to monitor the temperatures of chips in the back of the miner ensuring they don't go over 90°C as you're testing the frequencies. Sounds as though BitMain should have put the thermostat at the back of the unit because those chips get so much hotter. or smartly... run the fan from the back to the front ![Smiley](https://bitcointalk.org/Smileys/default/smiley.gif) Wouldn't doing that just make the other end of chips run higher? Whichever end is further from the fan will just run hotter, no?
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Vorta
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June 08, 2015, 10:18:47 AM |
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Vorta, did you do any fan mods?@
Yes, I have (ended up doing this). 2x Scythe Ultra Kaze (push-pull) has proven to be the best in airflow vs. sound ratio. You'll also be able to overclock your miner. Push-pull combination will always work better than any push-only configuration on the S5 because of a lot of air escaping the heatsink before reaching it's end. I would recommend not buying Deltas as they are very loud. I would also not recommend overclocking the miner while using only one fan. Unless you have an infrared thermometer to monitor the temperatures of chips in the back of the miner ensuring they don't go over 90°C as you're testing the frequencies. Sounds as though BitMain should have put the thermostat at the back of the unit because those chips get so much hotter. or smartly... run the fan from the back to the front ![Smiley](https://bitcointalk.org/Smileys/default/smiley.gif) Wouldn't doing that just make the other end of chips run higher? Whichever end is further from the fan will just run hotter, no? True, the thermometer is in the middle of the hashboard so whichever end the fan is on you get the same readout, but the chips next to the fan are colder than the readout, and chips on the back side are quite a bit hotter. The best solution would've been if there were 3 thermometers per hash board, one at each end and one in the middle.
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amelen
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![](https://bitcointalk.org/Themes/custom1/images/post/xx.gif) |
June 08, 2015, 12:58:03 PM |
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From a previous discussion, this was said to be the stock fan specs: Dimension: 120*120*38mm Voltage: 12V Start voltage: ≧8V (Power ON/OFF) Power consumption: 1600RPM 1.68W / 4000RPM 25.8W Rated current: DutyCycle 100% @ 2.15A Air Flow: 4000RPM @ 178.3CFM (Max be 239CFM) Noise: 4000RPM @ 56.7 dB-A (Measured in a Non-EchoChamber) Life Expectancy: 40,000 hrs @ 25℃ (May degrade faster at higher temperature) Connector: 2510-4P Also, I recently tried a dual 60CFM fan setup (one for push, one for pull), but it was clearly not powerful enough - temps were at 70C within a few minutes. This is what I used: http://www.newegg.com/Product/Product.aspx?Item=N82E16835553008I just ordered the following Delta and am hoping I can use it alone for just push: Delta Electronics AFB1212SHE 120x120x38mm Cooling Fan, 151.85 CFM, 58 dBA, 3700 RPM, 1.06 AMP, PWM 4-pin connector. I have the miners running in a temp controlled room with proper ventilation, which helps the temp's, but I'm still worried if the Delta might not be enough as 2x 60CFM was clearly not even close. @amelen That is a great find! Thank you. Please let me know what the results are!!!! Here's the fan on Amazon http://www.amazon.com/gp/product/B004Y1HLA8/ref=as_li_qf_sp_asin_il_tl?ie=UTF8&camp=1789&creative=9325&creativeASIN=B004Y1HLA8&linkCode=as2&tag=120mm-fans-20&linkId=5HKYNDGQB3P4D62ZJust replaced the stock fans with the Delta's from the amazon link. A few notes: - It's 4pin, but you still need to remove a piece on the connector to get it to fit in. - For some reason, I can't get them to be flush against the metal of the S5 like the stock fans. There is always a hair-thin space. - They are still pretty loud, but I'd say about 20-25% quieter than the stock fans. At full RPM, I'm seeing about 60dba, vs 75dba on the stock fans. - They aren't cooling as well as the stock fans, but it might be acceptable. At stock frequencies, with 22C ambient, I'm getting ~61C on the Delta and was getting ~56C on the stock fan.
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Evan
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![](https://bitcointalk.org/Themes/custom1/images/post/xx.gif) |
June 08, 2015, 01:09:27 PM |
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Push Pull? or stacked?
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I am poor, but i do work for Coin ![Smiley](https://bitcointalk.org/Smileys/default/smiley.gif) 1PtHcavXoakgNkQfEQdvnvEksEY2NvwaLM
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amelen
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![](https://bitcointalk.org/Themes/custom1/images/post/xx.gif) |
June 08, 2015, 01:42:12 PM |
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Push Pull? or stacked?
Just 1 delta as a push. It's specs were close to the stock fan, so I was hoping it would do the job. After about 1h of testing it doesn't look awful, however one S5 is overheating only on one side (the other one is proportionate). Not sure what could be causing it - the fans are identical and were installed exactly the same way.
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lemmyK
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![](https://bitcointalk.org/Themes/custom1/images/post/xx.gif) |
June 08, 2015, 02:03:07 PM |
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I use this: two pieces per S5 http://www.noctua.at/main.php?show=productview&products_id=78&lng=enSize 120x120x25 mm Connector 4-pin PWM Bearing SSO2 Blade Geometry Heptaperf™ Frame Technology FocusedFlow™ Rotational Speed (+/- 10%) 2000 RPM Min. Rotational Speed (PWM, +/-20%) 450 RPM Airflow 121,8 m³/h Acoustical Noise 29,7 dB(A) Static Pressure 3,94 mm H2O Max. Input Power 1,2 W Max. Input Current 0,1 A Voltage 12 V MTBF > 150.000 h Scope of Delivery Fan 4 Fan Screws Warranty 6 years Ingress Protection IP52 Material Fibre-glass reinforced polyamide Motor type Three-phase But if you want more cool so I recommend this already but the noise level is insufferable: http://www.noctua.at/main.php?show=productview&products_id=80&lng=en&set=1Size 120x120x25 mm Connector 4-pin PWM Bearing SSO2 Blade Geometry Heptaperf™ Frame Technology FocusedFlow™ Rotational Speed (+/- 10%) 3000 RPM Min. Rotational Speed (PWM, +/-20%) 750 RPM Airflow 186,7 m³/h Acoustical Noise 43,5 dB(A) Static Pressure 7,63 mm H2O Max. Input Power 3,6 W Max. Input Current 0,3 A Voltage 12 V MTBF > 150.000 h Scope of Delivery Fan 4 Fan Screws Warranty 6 years Ingress Protection IP52 Material Fibre-glass reinforced polyamide Motor type Three-phase These fans are expensive but indestructible. Corsair example, I broke when I accidentally tapped a finger in the propeller. when I have tapped into Noctua, much it hurts and fans held as of stone.
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amelen
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![](https://bitcointalk.org/Themes/custom1/images/post/xx.gif) |
June 08, 2015, 02:35:23 PM |
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I use this: two pieces per S5 http://www.noctua.at/main.php?show=productview&products_id=78&lng=enSize 120x120x25 mm Connector 4-pin PWM Bearing SSO2 Blade Geometry Heptaperf™ Frame Technology FocusedFlow™ Rotational Speed (+/- 10%) 2000 RPM Min. Rotational Speed (PWM, +/-20%) 450 RPM Airflow 121,8 m³/h Acoustical Noise 29,7 dB(A) Static Pressure 3,94 mm H2O Max. Input Power 1,2 W Max. Input Current 0,1 A Voltage 12 V MTBF > 150.000 h Scope of Delivery Fan 4 Fan Screws Warranty 6 years Ingress Protection IP52 Material Fibre-glass reinforced polyamide Motor type Three-phase But if you want more cool so I recommend this already but the noise level is insufferable: http://www.noctua.at/main.php?show=productview&products_id=80&lng=en&set=1Size 120x120x25 mm Connector 4-pin PWM Bearing SSO2 Blade Geometry Heptaperf™ Frame Technology FocusedFlow™ Rotational Speed (+/- 10%) 3000 RPM Min. Rotational Speed (PWM, +/-20%) 750 RPM Airflow 186,7 m³/h Acoustical Noise 43,5 dB(A) Static Pressure 7,63 mm H2O Max. Input Power 3,6 W Max. Input Current 0,3 A Voltage 12 V MTBF > 150.000 h Scope of Delivery Fan 4 Fan Screws Warranty 6 years Ingress Protection IP52 Material Fibre-glass reinforced polyamide Motor type Three-phase These fans are expensive but indestructible. Corsair example, I broke when I accidentally tapped a finger in the propeller. when I have tapped into Noctua, much it hurts and fans held as of stone. What temp's are you seeing with those fans?
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Evan
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![](https://bitcointalk.org/Themes/custom1/images/post/xx.gif) |
June 08, 2015, 03:01:07 PM |
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Push Pull? or stacked?
Just 1 delta as a push. It's specs were close to the stock fan, so I was hoping it would do the job. After about 1h of testing it doesn't look awful, however one S5 is overheating only on one side (the other one is proportionate). Not sure what could be causing it - the fans are identical and were installed exactly the same way. Can I see Pictures
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lemmyK
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![](https://bitcointalk.org/Themes/custom1/images/post/xx.gif) |
June 08, 2015, 03:38:59 PM |
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I use this: two pieces per S5 http://www.noctua.at/main.php?show=productview&products_id=78&lng=enSize 120x120x25 mm Connector 4-pin PWM Bearing SSO2 Blade Geometry Heptaperf™ Frame Technology FocusedFlow™ Rotational Speed (+/- 10%) 2000 RPM Min. Rotational Speed (PWM, +/-20%) 450 RPM Airflow 121,8 m³/h Acoustical Noise 29,7 dB(A) Static Pressure 3,94 mm H2O Max. Input Power 1,2 W Max. Input Current 0,1 A Voltage 12 V MTBF > 150.000 h Scope of Delivery Fan 4 Fan Screws Warranty 6 years Ingress Protection IP52 Material Fibre-glass reinforced polyamide Motor type Three-phase But if you want more cool so I recommend this already but the noise level is insufferable: http://www.noctua.at/main.php?show=productview&products_id=80&lng=en&set=1Size 120x120x25 mm Connector 4-pin PWM Bearing SSO2 Blade Geometry Heptaperf™ Frame Technology FocusedFlow™ Rotational Speed (+/- 10%) 3000 RPM Min. Rotational Speed (PWM, +/-20%) 750 RPM Airflow 186,7 m³/h Acoustical Noise 43,5 dB(A) Static Pressure 7,63 mm H2O Max. Input Power 3,6 W Max. Input Current 0,3 A Voltage 12 V MTBF > 150.000 h Scope of Delivery Fan 4 Fan Screws Warranty 6 years Ingress Protection IP52 Material Fibre-glass reinforced polyamide Motor type Three-phase These fans are expensive but indestructible. Corsair example, I broke when I accidentally tapped a finger in the propeller. when I have tapped into Noctua, much it hurts and fans held as of stone. What temp's are you seeing with those fans? 55 degrees Celsius in the room where it is 22 degrees or less. but even if they increased the room temperature at 30 is really not more than 65 on S5.
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amelen
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![](https://bitcointalk.org/Themes/custom1/images/post/xx.gif) |
June 08, 2015, 03:52:44 PM |
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Push Pull? or stacked?
Just 1 delta as a push. It's specs were close to the stock fan, so I was hoping it would do the job. After about 1h of testing it doesn't look awful, however one S5 is overheating only on one side (the other one is proportionate). Not sure what could be causing it - the fans are identical and were installed exactly the same way. Can I see Pictures I had to remove the black screws to get the Delta to fit flush. One unit running 60C/60C, the other 63C/55C, still not sure why it's uneven. The heatsinks got slightly bent while I was taking it in/out, but I got them almost back into the stock position. Not sure if the heatsinks would be causing such a temperature imbalance? ![](https://ip.bitcointalk.org/?u=http%3A%2F%2Fwww.alexmelen.com%2Fbitcoin%2Fs5-2.jpg&t=665&c=hVnQaUK6RIV1-w)
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Crypto84
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![](https://bitcointalk.org/Themes/custom1/images/post/xx.gif) |
June 08, 2015, 04:04:59 PM |
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anyone know the size screws needed for the stock fan? gonna add a pull fan to the back. wanted the same screws.
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Evan
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![](https://bitcointalk.org/Themes/custom1/images/post/xx.gif) |
June 08, 2015, 04:11:22 PM |
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anyone know the size screws needed for the stock fan? gonna add a pull fan to the back. wanted the same screws.
Just take 2 from the front to mount on the back
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I am poor, but i do work for Coin ![Smiley](https://bitcointalk.org/Smileys/default/smiley.gif) 1PtHcavXoakgNkQfEQdvnvEksEY2NvwaLM
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