Yes!madhorsefuzzy wrote:Very good initiative!!!
Can you measure the fans at 5V, 7V and 12V also because many of us are using the fans at 5V or 7V without a fan controller?
It's VERY important, to have such data.
No, it's the little brown resistor & black transistor pair that need to be cooled, the fan is blowing sideways on to them. There's another pair of the resistor & black transistor on the right, above which is a space for a similar little blower fan. It has to be some kind of clamp heatsink that will press against both the transistor and the resistor, big enough to dissipate the heat. I just haven't had time to scour through my parts bins (not likely to have anything quite right) or visit the local electronics parts stores.KayDat wrote:Wow, that looks nice. Could you fit a northbridge/chipset cooler in there?
I was just looking at the code behind this interactive graph and it's not as slick as it looks. The line graphs were statically defined. For example, here are two of the lines which get layered on top of the background image (prepend the website name since I cannot post links):MikeC wrote: btw, we need some help with a bit of coding for our fan articles. Please see this:
That type of interactive chart would be wonderful for us to use for measured fan data. Can anyone help us develop a similar function?
We did report that in previous reviews but not sure whether we'll bother in future -- the power is minuscule esp. for slow fans. Typically no more than a watt.guerby wrote:Hi,
Do you have by any chance measured the amp taken by the fans? We have voltage but no way to get to the watt consumed by the fans .
Thanks!
Remember that we are not comparing heatsinks, however.trident wrote:Great article Mike, very informative.
I have a question.
As you stated in the article, thermal systems (heat source, heat-sink and fan) are very difficult to model. As an example: heat-sink 'X' may out perform heat-sink 'Y' with a 137W input, but the reverse can happen at a different heat input. This is because the thermal resistance of a system is not a constant, it varies with the amount of heat flowing through the system as well as the temperature at the input and the temperature at the exit point.
Well, yes it is that.... but it's also generally indicative of how each fan would do on many heatsinks. The 137W input is not equal to a 137W processor, i7 or otherwise, for reasons discussed in the article. I'd guess it's closer to a <100W TDP processor.trident wrote:Rather than a measure of general performance, won't the fan ratings be more reflective of which is the best fan to use on a Thermalright Ultra 120 Extreme with a 137W input?
Thanks, I found watt values here:MikeC wrote:We did report that in previous reviews but not sure whether we'll bother in future -- the power is minuscule esp. for slow fans. Typically no more than a watt.guerby wrote:Hi,
Do you have by any chance measured the amp taken by the fans? We have voltage but no way to get to the watt consumed by the fans .
Thanks!
It was there for 11 days, and read >12,000 times, enough, I thought. It's at the top of the fan section and also in the recommended/reference section. If you think it should go back to the front page for longer, that's easily done.NeilBlanchard wrote:Why is there no link to this article on the front page anymore?
You must not be familiar with speedfan. Try reading viewtopic.php?p=513736 and see if you still feel that it's easier to control voltage than a software controlled percentage.Erelyes wrote:To me it seems easier for a home user to set a fan to run at a specific voltage, than to get it to run at a specific RPM.
frostedflakes wrote:I think it might be worthwhile to measure open-air FPM, because that would probably be pretty relevant for people who want to use them as case fans or in other situations involving low static pressure.
Original testing method used impeller anemometer and it was proven unreliable method for measuring fan's airflow. This excellent article discussed that:Erelyes wrote:Here's an "outside the box" idea for measuring a fan's performance as a case fan - set up a computer case as a test rig, with a single 120mm intake fan in the lower front, and measure the FPM at the exhaust in the top rear of the case. Seems to me that'd give a fairly accurate idea of the fan's performance in what we actually want it to do (move air in a large area).
So what practical implication does this have on the quiet-seeking PC builder or modder? What we've been saying all along for years:
* Choose the quietest fan with the best noise signature and adjust its speed to give a balance of cooling and noise you can live with.
* Don't worry about CFM. Just go for the quietest fan and the best low-airflow performance heatsink, and minimize airflow impedances in your case.
It's funny, but true: We went through this entire rigamarole of establishing an accurate system of measuring axial fan CFM only to tell you it doesn't really matter, and not to worry about it.
That's really what it comes down to. When PC enthusiasts start trying to fully understand and model fluid mechanics (yes, air is a fluid), the discussion starts to get a little out of hand. For silent computing, choosing a fan with desirable sound characteristics is far more important than trying to classify fans based on airflow and pressure: it's just too complex!MikeC wrote: I really don't give a hoot about airflow measurements because they're just distractions.
That's my concern too, but for a completely different reason!dev wrote:Good initiative Mike. The only thing I'm concerned is the TRUE choice for the reference heatsink. ...
The solution is to use a solid metal heatsink where the thermal distribution will be consistent no matter what temperature range you're operating at.gojira wrote:... the exponential drop in cooling performance as the cooling ability of the heat exchanger as a function of airflow goes pear shaped. As the fans get closer to that point ... you are no longer able to compare the fans. This was demonstrated quite well in Ehume's fan review at overclock.net. The temperature differences between fans as the "temp rise" approached 50c became so small that it was hard to tell how much more "work" a fan was really doing. ...
Some of them most definitely do provide such curves. The data sheets from EBM-Papst are for example very informative.Cynyr wrote:I wish ... Fan manufacturers would provide fan curves (rpm/power/cfm/pressure drop) ...
Well you could just take the heaviest heatsink you want and take side cutters to the heat pipes to separate them from the base.Olle P wrote:This is a rig for testing fans, not heatsinks, so there's no need to bother about what's available on the market.
With a solid heatsink you don't need that much power to reach the same temps.
Cheers
Olle