I honestly don't understand the hoopla surrounding the TMD fans.

Let's see now... they do two flavours of this fan, one 34.2dBA (loud) and the other 38dBA (much louder). Even the "high-flow" version flows only 36CFM. The 80mm H1A flows 39.6CFM at 32dBA and is cheaper to boot. (at 2cooltek atleast)

So it has a marginally bigger hub. BFD.

Static Pressure... this looks better.
5.755mmH2O for 5800rpm TMD (from a review on the net).
3.78mmH2O for the H1A (from Panasonic's site).

I still don't get it - its not that great a fan, and 38dBA is pretty damn loud. I certainly wouldn't be able to stand something like that next to me all the time.

Anyway, its one of those new things everyone's gotta have. I'm happy with my SK-7 and L1A keeping my 1700+ overclocked to 8.5x200 at 37-38°C load.

The only interest of TMD fan is the minimum central obstruction it provides. On CPU heatsinks, it can be interresting to blow air on the center as it is where the die is.

BaD CrC said:

The only interest of TMD fan is the minimum central obstruction it provides. On CPU heatsinks, it can be interresting to blow air on the center as it is where the die is.

Click to expand...

No, this is not true. Mark's point about the static pressure is right on target. Static pressure is an important factor in CPU cooling applications. Static pressure drops as we build a progressively larger fan blade for a given airflow. So TMD fans allow a slightly smaller fan blade for a given airflow rate, producing better static pressure characteristics. This matters not to case fan applications, but is a big deal in CPU cooling. This is why the old 60mm Delta screamers are so effective. They are only 38 cfm, but have termendous static pressure... and god-awful noise.

The effect of the dead spot can be largely overcome by intelligent heatsink design. The AX-7/478, and the Vantec Aeroflow have large chunks of aluminum underneath the dead spot rather than fins. This provides important thermal mass for the die, making it an intelligent work-around of the dead spot.

Personally I don't use the TMD fans because I also feel 80mm fans like the Panaflo have better noise characteristics, but make no mistake, we sacrifice static pressure in the bargin. For heatsinks with widely spaced fins, static pressure may be the thing most attractively sacrificed, but for designs with closely spaced fins (V7+, SLK800) the smaller and faster spinning fan will always be the best performer, even if it does assault the ears.

OK Mark, on an SK7 heatsink, the 30cfm TMD fan performs on par with a 39cfm 80mm Sunon, noisewise they are similar, my temps with either are identical. With the 36cfm TMD my temps are 2 deg C cooler than with the Sunon, and I don't find the noise to be all that intrusive. I think these things have actually been available for quite awhile now, maybe even over a year, and I've been quite pleased with the performance/noise ratio.