My TMD fan test results

[arman68]

I ordered a YS-Tech TMD fan yesterday to see if it would make any improvement by replacing my existing fan on the heatsink. Received it this morning and just finished conducting some quick tests.

Specs

As you can probably see from my signature I am using a P4 2.0a overclocked to 2.5MHz, CPU cooling is provided by a very basic CoolerMaster IAC-002. The heatsink is all aluminium, nothing special. The fan that came with it is a Delta (not the screaming kind). Let's compare both fan specs:

Delta AFB0712HHB 70x70x15mm
RPM: 4300
CFM: 37
dBA: 38
3.35W / 0.28A / 12V

YS-Tech TMD PD1270155B-2F 70x70x15mm
RPM: 5600
CFM: 38
dBA: 37
3.70W / 0.308A / 12V


Test setup

Constant ambient temperature of 23°C

All additional fans on Zalman brackets have been removed to prevent interference. Computer case closed :)

I measured the temperature after 10 minutes of idle time, and 10 minutes of Prime95 Torture Test.

When I tried replacing the Delta fan with the TMD I was faced with a major problem: even though the TMD fan is supposed to have the same dimensions as the Delta, it does not! If you look at pictures of TMD fans you will notice they are slightly rounded on all 4 sides... Well, that exceeds 70mm. For my setup it meant I could not fit the fan properly on the heatsink, due to the retention brackets forming a slot for the fan.

What I did instead was to use longer screws to position the fan sligthly above the heatsink, with a 10mm gap between the top of the heatsink and the bottom of the fan. Fan was slightly lose but that's allright (lucky I did not use Arctic Silver 3 ;) )


Test results

Delta fan
idle: 38°C
load: 50°C

YS-Tech TMD fan
idle: 38°C
load: 51°C


Conclusion

The TMD fan did not perform as well as I expect it should, but my results are biased by the fact that I had a 10mm gap between the TMD fan and the heatsink: it means the airflow loses some strength and is not forced into the fins gaps anymore.

I still believe that if the TMD fan can be mounted properly it would have a big impact due to more airflow reaching the CPU core.

Unfortunately the TMD fan can only be fitted on a heatsink with a totally flat top.

[JFettig]

that is very interesting... it could be a flaw tho... try testing it again, and if you dont feel you want it id love to take it!;)

[Mizzery]

Am reading the specs right that one only has one cfm more than the other? You're probabally loosing more than that due to you gap.

[jkos]

Originally posted by Mizzery
Am reading the specs right that one only has one cfm more than the other?

Keep in mind that CFM isn't the only parameter that counts. It is also the CFM versus static pressure curve of the fan that counts.

For example, someone was able to get better cooling with a 10 CFM blower than with a 38 CFM axial fan. Why? Because blowers maintain their flow rate much better as the static pressure increases, thus, they are able to actually push the air through the heatsink much better than an axial fan.

It would be very interesting to do some real measurements of the actual CFM obtained through various heatsinks by various fans.

- John

[macklin01]

arman68,

Thanks for some results -- a lot of us have been waiting to see these in action! Two questions:

1) Where did you manage to order the fan separately?

2) Could you please scan a pic of the fan to point out where
the curve is giving troubles? Thanks! -- Paul

[arman68]

Got the fan in the uk from ocuk at http://www.overclockers.co.uk/acatalog/Online_Catalogue_YS_Tech_Fans_60.html

There are a couple more of online oc shops that carry it in the uk (the high speed version).

I have not got any pictures, but if you look at the Dan's Data article on http://www.dansdata.com/tmdfan.htm you'll notice the curve I am talking about.

Actually after looking at the above article again, I think there is a possibility that the TMD fan would fit if I can remove the metallic cover... I will try tomorrow.

[macklin01]

I see what you mean. It's too bad they curved it -- it appears to be purely aesthetic...

Thanks for the sites. Anybody know any in the US? ...

Thanks -- Paul

[arman68]

No more TMD fan... :(

After much effort I managed to separate the metallic cover from the fan+engine. This proved to be much more difficult than expected as the 4 electromagnets at each corner were glued to the metallic cover! When you look at the pictures on Dan's Data, there is no trace of glue. I had to pry mine open very carefully with a thin blade and managed to do it without severing any of the cables.

I ran a quick test by plugging the fan in a mobo header, it worked fine.

Next step was to fit the TMD fan on the heatsink, without the metallic cover. I had to dismantle the mounting brackets and after much effort finally managed to have everything fitted properly on my CPU. This was a very tight fit though. :)

Time to test: plugged the fan in the CPU mobo header. Plug in the power supply. Press the on button. Holy cow, the fan jerked a bit an did not start and smoke started coming out of the motherboard header :eek:

I pulled the plug as fast as I could. I expect the TMD fan metallic cover must have served a purpose of shielding and without it the fan was shorted by being to close to the metallic mounting brackets.

At this stage I thought I'd be lucky if I could get out of with just a mobo header out of use... :cry:

Time to remove the TMD fan and put back the original one and check what is still working...

Did I mentioned the fit was very tight? Well actually it was too tight. There was no way to remove the heatsink, let alone the mounting brackets... In the end I had to decide cut out the TMD fan. Not unlike a fireman trying to free trapped people from a vehicle ;) Once done I put back the original fan and threw all the bits of the TMD fan in the bin...

Checked the mobo header with a spare fan: I could not believe it was still working! Abit has really build the TH7-II with overclockers in mind.

I am now back to normal and happy that my computer survived.

Shame that YS-Tech decided to curve those fans.

[macklin01]

arman68,

Thanks for your report. I'm really, really sorry to hear what happened, but I'm glad that things turned out well; I had feared the worst!

So, did the windings contact the HS and cause the short?

Thanks again for the info -- Paul

And agreed: shame on YS for putting aesthetics above function. :mad:

[klosters64a]

I noticed the curve in pics of the TMD fan. My Q: WTH is this thing a 70mm fan? Seen any 70mm HS's?

[macklin01]

Originally posted by klosters64a
I noticed the curve in pics of the TMD fan. My Q: WTH is this thing a 70mm fan? Seen any 70mm HS's?
I think most P4 heatsinks are moving in that direction ... -- Paul

[arman68]

I think the windings were clear.

What must have caused the short is one the electric cables running all the way round, from winding to winding, making contact with the metallic heatsink brackets. I thought I had tucked those cables away carefully but apparentely not :(

To be 100% safe I should have used electrical tape to insulate the whole lot.

[Hookem]

newegg has the heatsink and fan for 18 bones ... I just want the 80mm case fans ... well a 80 for the Alpha 8045 would be nice too !!! Anybody know where to get em ???

[macklin01]

I don't think they're available yet. YS-tech was to release the 70mm version first for the p4 HSF, then separately, then followed by 60mm and 80mm. I think they're behind their timeline.

-- Paul

EDIT: their info can be found at
http://www.ystech.com.tw/Tmd/tmd-3.htm