Does a CPU really need a fan?

Dr Yeti

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May 21, 2013
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Chances are that unless your case is exceptionally well vented and you have a heat sink specifically designed to be fanless, your PC will MAYBE be OK at idle, but will certainly hit its thermal max and shut down under any kind of load. Are you building a new rig or are did your fan break?
 

elemein

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Mar 4, 2013
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Depends. Some CPUs are fine and others arent.

Full power desktop CPUs usually run way too hot for all but the largest heatsinks to effectively cool.

However, many lower power processors are fine without fans. Most Intel Atom machines run fanless. Most AMD Bobcat machines run fanless. A lot of AMD E-series machines run fanless, like my dad's HTPC. A lot of ULV Intel mobile CPUs run fanless in desktop or tablet environments. A lot of ULV AMD mobile processors run fanless as well.

Otherwise, the CPU will almost always need a fan.
 

thasan1

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unless you want to see how a melted CPU chip looks like its quite important. but many low powered CPU won't actually need one like mobile CPU's. but its still necessary. but you wont actually need a large heatsink. stock one will do jusyt fine if your aren't OCing.
 

random stalker

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Feb 3, 2013
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depends...

Check the TDP - it's a value that refers to the maximum amount of power your cooler needs to dissipate.
The more you have, the better cooling you'll need to have.

Take a nofan-cr100a cooler - it has no fans (as the name says) and can cool anything under 100W of TDP.
BUT! There is a big BUT! you'll need a good vented case, so the heat can escape.

Example - let's say the 95c cooler will cool your 95W CPU at about 50oC above ambient temperature.
You have about 26oC in your room, so the CPU will run at 76oC. Which is nice...
Now. If you have a badly vented case, the temperature inside rises inside to... let's say 40oC...
And your CPU will fry at 90oC and shuts down....

FYI - a Noctua ND-14 /a nice cooler with fans/ would cool the same processor at about 15-19oC above ambient.
 
YES op, cpu fans are necessary unless you've got a low TDP cpu and a heatsink designed for fanless operation and a case with good airflow. I wouldn't bother going fanless...

the best option would be to get a highly efficient intel cpu with a low TDP, stick a Thermalright HR-02 Macho onto it, hang a noctua onto the macho, and run it as slow as you can. You'll never hear the fan (it will be under 20db, which is about the threshold for human hearing, background noise is typically 30db) and you'll never be at risk for melting your cpu/mb.

the poster talking about the nofan is offering good advice as well. however, i wouldn't use a nofan with an AMD cpu. amd cpus are too temp sensitive. You also need a case with a big mesh vent directly above the cpu, and a motherboard with enough room so the nofan doesn't block your first pci-e slot (most mbs have their first pci-e slot blocked by it)... overall i'd put more trust into a HR-02 with a silent fan like a noctua hanging from it.
 

logainofhades

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I ran a core 2 E8190 @ 3.8ghz on an old thermaltake DIY tower cooler without a fan other than case fan that sat fairly close behind it without issue. If the cooler is up to the task and you have proper airflow, it can be done. I wouldn't recommend it with anything over a dual core though.
 

random stalker

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well, I guess the question: "which CPU do you have?" should be in order here... second will be: "do you have a desktop or a tower?". Third is: "how good is your case vented?"

But I fear your setup as it is now wouldn't handle it.
From the picture there, the fins are very close to each other - which is bad business.
But you can try to set your fan speed to absolute minimum, run prime for half an hour and watch the temperature. If it rises high, then it is definite - in order to have a silent PC you'd need a better case and a fanless cooler :D

PS: For the guys above. The CPU-burns-to-crisp joke is already 6 years old... Come on guys, find another way to trash AMD, this is no longer funny... The reference vid> http://www.youtube.com/watch?v=yRn8ri9tKf8
 


No... i wasn't trashing AMD, just pointing out a small issue with using a fanless system with an AMD.

The AMD chip is a chip designed to run COLD. as in you dump NO2 onto it and it won't break and will overclock like a god. Intel chips can't do that. The tradeoff is at around 65C AMD cpus start to break down. they can't run hot like an intel can.

If you're going fanless you need 2 things. 1) you need a low TDP chip. Intel chips in general are much lower TDP then AMD for the same performance.
2) you need a chip that can run hot safely. Intels can run up to 90C or so before they start to overheat. Which means they're ideal for a fanless heatsink

this isn't "trashing AMD", this is just the objective facts about the situation. I remember watching some dude overclock an i5-2500k up to 4.6ghz on a nofan, his cpu ran up to 90C... and all i could think is "wow, the nofan is f-ing awesome..." and then thinking "i can't do this with an AMD"... the nofan is more effective the hotter the cpu, unfortunately you can't really use it with a performance AMD unless you underclock it.
 


you're already running at 60c with the fan running?

nope. you won't be able to run fanless. frankly you're running too hot WITH the fan. What i mean is your overclock is not extreme, you should be running cooler then this (not that it's a dangerous temp, just that your cooler should be working better then that)
 

random stalker

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+1

Considering the i5-750 has a base clock speed of 2.66GHz and a TDP of 95W as it is stated here, you'd have to stop OC the processor to have even a remote chance to cool it passively... And if, it would be very hard (not impossible though)...
Sorry...