Rad Fan Question

Puppetmaster

Puppetmaster

Puppetmaster

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I currently have my radiator mounted at the bottom of my case, with 2 fans sitting on top (pulling air through)

If i added 2 fans pushing air through below the rad, would it reduce temps much?

My radiator isnt fixed it just sits on the bottom grille but im considering adding 2 more fans.
 
Adding extra fans will always help, but don't expect massive differences. But in all honesty if it won't cost u a lot, its always worth testing it urself.
 
Currently with my cpu @ 3.8GHz using 1.328v from cpu z, after an hour of prime maximum head cpu cores are 65 60 63 61 with side of case off. I need to reseat my block because core 1 is always higher since i last reseated it. Im only using a 120.2 rad.

Ive got a few spare fans so will try adding tomorrow. I could do with something to put underthe fans on the case, to stop any vibration. Any ideas?
 
Puppetmaster said:
Currently with my cpu @ 3.8GHz using 1.328v from cpu z, after an hour of prime maximum head cpu cores are 65 60 63 61 with side of case off. I need to reseat my block because core 1 is always higher since i last reseated it. Im only using a 120.2 rad.

Ive got a few spare fans so will try adding tomorrow. I could do with something to put underthe fans on the case, to stop any vibration. Any ideas?
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Maybe a gasket or fan filter or guard or something like that might help?
 
:confused: those temps look fine if thats an i7 cpu. Doubt you will get much better than one or two degrees when running prime.
 
Thats with a Core 2 Quad with the side off @ night. during the day its hotter and with the side on raises temps by a few degrees. Also going to have to use more volts to get to 4GHz so will again raise temperatures. Not to mention my room feels really hot at night so want to try to drop temperatures a bit. After running for several hours, temps got up to about 68 - 70.
 
Puppetmaster said:
Not to mention my room feels really hot at night so want to try to drop temperatures a bit.
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:confused:

The heat still will get dumped into your room no matter how many fans or radiators you use. Watercooling doesn't absorb the heat from your components and turn it into cool air, it transfers the heat efficiently to the radiators and the fans blow it from the radiator fins into the room.

If the room isn't sufficiently ventilated or airconditioned the heat from the radiators will start to raise the ambient temps.

You may want to rethink running at full speed overnight at those frequencies/voltages if a primary concern is ambient room temperatures.

Back on topic, Martin at Skinee Labs did a great test of shrouds, and fans and fan orientation that will help you here

Here is the summary for those not bothered to go check it out :D

TFC Shrouds and shrouds in general - Always provide a good performance benefit and reduce noise at the same time. Highly recommended in all radiator setups particularly for higher speed fans unless the space does not make them an option. You can see as much as 10-16% gains on higher speed 38mm fans and 6% gains with slow speed fans. Generally the higher the fan speed and the larger the fan hub, the more gain you will see with shrouds. Optimal depth appears to be somewhere around 30mm +-, this is likely to depend on hub diameter and RPM to some extent.

Push Vs Pull - This depends on fan speed/power. The high speed fans at 2000RPM with a 38mm fan thickness provided the best performance in a push condition. The slow speed fans with 1350RPM with a 25mm fan thickness provided the best performance in a pull condition. I would estimate that performance line is likely to cross in the 1500-1700RPM range where they are equal. So.... slow speed = pull, high speed = push, medium speed = it doesn't really matter.

2 fans Push/Pull vs others - It was very clear that when using two fans per radiator section, that the radiator intself acts as a flow spreader and provided great benefit to straightening out the air for the second fan in a push/pull configuration. Just like doubling up with a pump, there is a pressure benefit to doubling up on fans and this translates to about a 20-30% performance gain. The added fan pressure simply means and added gain in air flow and corresponding performance. None of the experimental pull/pull or push/push configurations provided any noteworthy benefit as it seams the air is simply too disturbed from the first fan to allow the second to perform properly when air is moving. I would always recommend a push/pull configuration for two fans and add a shroud to both sides if space allows.
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I was only running those temps overnight testing for prime stable.


Surely if my cpu is running at 80 degrees, its producing hotter air than @ 50 degrees? Atleast the air coming out of my radiator feels cooler when its at idle rather than full load.


Not to mention higher cpu temperatures will raise the whole loops temp, increasing my graphics cards temp as well. Im trying to overclock that some more than i have already and temperature could hinder that.
 
Puppetmaster said:
I was only running those temps overnight testing for prime stable.

Surely if my cpu is running at 80 degrees, its producing hotter air than @ 50 degrees? Atleast the air coming out of my radiator feels cooler when its at idle rather than full load.

Not to mention higher cpu temperatures will raise the whole loops temp, increasing my graphics cards temp as well. Im trying to overclock that some more than i have already and temperature could hinder that.
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Uh no mate, sorry thats not how it works, your CPU is producing XXX Watts of energy which is radiating in terms of heat into the system. The water cooling isn't actually reducing the heat being generated by the CPU it is just removing it from the CPU faster than say the stock cooler or an air cooler.

Think about it. When your CPU is idling its using less watts, when its running at 100% its using more watts. Watts used equates to energy which in CPU's gets transferred to heat output at an almost 1:1 basis.
 
Well i removed the vent from my bottom of my case and fitted 2 extra fans under the rad. Load temps atm not gone over 57 52 54 53 but its a bit cooler at the moment. Still looks like its giving me an ok decrease in temps.
 
Yup, thats what it should do :) I think the research is somewhere between 10-20% reduction with push/pull. (depending on a lot of factors) Looks like you went from 65 to 57 on the hottest core which is a pretty good drop :)

The only downside to push/pull is that it can increase noise, thats when using an old fan housing as a shroud can give you slightly less drop in temps for a significant drop in noise.

But result! :D
 
Not really noticed much noise. Used some handy blu tac to sort any vibration issues out lol. Working well. I think i need to reseat my cpu block as the 1st core was never really hotter than the rest, but now its a good 3 - 5 degrees higher.
 
Well after about 1hr 1/2 @ 1.336v with my cpu @3.9GHz temps max are 64 57 61 60. Hopefully i wont need any more volts for 4GHz :p but alteast my cooling change is helping.
 
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