Fans to psu? Help

[xjtaggedx]

Hello guys..

I am moving a Dell 3010 ssf to another case.. I have modded the case here and there..

I am in the process of purchasing 3 fans.. 12v 0.25.. I have 3 other fans but only at 12v 0.15.. I do not know if they will be powerful enough.. bare in mind the ssf case only had one other than the CPU fan..

My question is how do I contact the fans directly to the PSU?..

Thank you in advance..

Great forum..

 

[jamz4]

fans will have a small 3 or 4 pin connector that plugs into the motherboard fan header. In some older models it may have a molex connector. Any that have a molex connector can be plugged into the PSU's molex connections. Fans with 3 or 4 pin connectors can use splitters (a connector to the motherboard that will split into 2 or more connections) or you can find cheap molex to fan adapters online if there aren't enough on the motherboard.

examples:

https://www.amazon.co.uk/Akasa-AK-CBFA04-15-Splitter-Cable-Fans/dp/B005FWXWPS/ref=sr_1_4?ie=UTF8&qid=1540217211&sr=8-4&keywords=fan+splitter

https://www.amazon.co.uk/KabelDirekt-20-20-20cm-3-pin-2-pole-connector-fan-distribution/dp/B01LFCB3TS/ref=sr_1_2?s=computers&ie=UTF8&qid=1540217244&sr=1-2&keywords=molex+to+fan

 

[xjtaggedx]

Thank you for posting kind sir.. unfortunately it's a Dell and they use strange 5pin fan connectors so I can get a converter for a 5 to 3 pin for the CPU fan.. not an issue..

The second link you provided looks good.. do you know.. when it says 12v.. is that 12v over the 3 fans or 12v per fan?..

Thank you

 

[william p]

Your best option would be to use a Dell 5 pin fan. Dell uses the same industrial grade fans they use in their servers and workstations in their office computers.
Look at the Amperage rating of the original fan and find one that is around that capacity in the size you need now. Dell 120mm fans tend to be 38mm thick. Aftermarket are 25mm. It makes a huge difference in airflow. Dell fans tend to run from .9A. to 1.8A although I would hesitate to put a 1.8A fan where a .9A. was before.
If you just have to use those cheapa$$ fans you can splice a Dell plug onto them if you learn the Dell 4/5 wire pinout.
https://forums.anandtech.com/threads/dell-motherboard-cpu-fan-header-question.2489271/

 

[xjtaggedx]

I have been considering using the original heatsink and fan the only issue is it will not fit as is and I would have to heavily modified it to work.. I believe it is about 1.2A..
Really the issue I am having is the other fans I have purchased for the build..

 

[william p]

The 3 wire fans have no speed control except for the Voltage supplied to them. On 12V. They will run 100% all the time. The third wire is just to monitor speed. 12V. and GRD will run them. The 4 wire fans have a speed control PWM wire added. If that's not connected they will run 100% also. They may be loud since they're intended to run at 30-40% speed most of the time.
There are adapters available.
https://www.ebay.com/p/1pcs-5-Pin-Dell-Latch-Fan-Connector-to-4-Pin-Fan-Adapter-Convertion-Cable/529924955?iid=262784103218&chn=ps
Since you're rpelacing a 1.2A. fan (normal for a Dell) you should be able to slpit several aftermarket fans off of this adapter. They willl all run relative to CPU temperature unless they're 3 pin then they will run full speed.

 

[xjtaggedx]

Thank you for your reply..

This is very interesting to me and I am able to understand more due to your explanation.. thank you..

May I ask.. when you say full speed as in 100%.. that is subjust to the amps on the fan itself?.. for instance a fan with 0.15a Vs a fan with 0.25a.. the latter fan will spin faster?..

 

[william p]

Fans are actually very complex due to air being compressible. Number of blades, their shape the pitch angle all factor into it. 100% speed in free air, and 100% speed against a radiator will be different. There are 3 blade to 11 blade designs. Generally the bigger diameter fans are slower and quiter for the same air flow. But a low Amp fan can only do a certain amount of work. Thicker fans can accelerate the air over a longer distance if they have the extra power to do it.