Dynatron DC1206BM-L/638

Very good performance but with lots of noise. –Joe

SUMMARY: The Dynatron DC1206BM-L/638 is a skived, aluminum heatsink shows very good performance with Delta’s incredibly noisy 44 cfm fan, and good performance with YS Tech’s 40 cfm fan.

OCZ Dominator

Weight: 287 grams; Dimensions, Heatsink Only: 62 x 63 x 36 (mm – L*W*H); Pic with Delta 44 cfm fan.

Dynatron was nice enough to send us a sample of the Dynatron DC1206BM-L/638 It’s an all aluminum unit with 40 fins. The heatsink has “skived fins”:

OCZ Fin Detail

Note that the fins are lifted from the base.

This is a new technique that literally shaves fins from the base material. The advantage is that there is no mechanical bond, such as soldering, between the fins and the base – it’s all one piece – effectively eliminating any thermal degradation due to the bond used between the two. Compared to a heatsink that mechanically crimps fins into the base, skiving can show markedly better performance. This technique is also being used for copper heatsinks.

Composite Fin

This pic is a composite shot showing both sides of the fins. One side is smooth and the other has a “pebbly” consistency. I am guessing that as the fin is lifted by a knife blade (smooth side), the side opposite the blade “crinkles” as it lifts off the base. A very interesting process!

Dyn Side

The side shot shows overall fin density – the shroud is screwed onto the base and is removable.

Dyn Top

Looking down into it gives some idea of the “fan challenge” – the fan used for this heatsink must generate enough pressure to push air through the fins. I think this almost forces the use of a Delta 38 class or better fan. Unfortunately, this means that noise becomes an unwanted by-product.


The 60mm 44 cfm Delta (left) is 38 mm compared to the familiar 25mm.

Dynatron offers three fans – the Delta 44 cfm, 38 cfm and a 24 cfm unit (not tested) – If you think the Delta 38/clones are loud, the Delta 44 is much worse. In this test series, I used the YS Tech 40 cfm fan along with the Delta 44.

I measured noise with a Radio Shack Sound Meter 8″ from the fan’s intake – the YS Tech @ 72, the Delta @ 77 dBA. The latter is REALLY objectionable, except maybe if you use it in a jet engine test facility.


The 44 cfm Delta has vanes in the bottom which direct airflow such that it blows straight down into the heatsink; airflow from other fans will show a more radial pattern as air exits from the blades.


The Delta is rated at 0.83 amp per the label – this is 10 WATTS. Most motherboards support, at best, 5 watts. Running the Delta 44 on a motherboard fan header will most likely burn it out pretty quickly.


The bottom show definite machining marks, although these are very fine.

The clip is the “OEM” type – you must use a screwdriver to mount it on the socket.


I prepared the Dynatron by boring a hole completely through the base so I could epoxy a thermocouple above the CPU. The thermocouple is attached to an Omega HH23 Digital Thermometer. Ambient temps were measured with a thermocouple placed about 1 inch from the fan’s intake. I used Prime 95 to stress the CPU on an Iwill KK266, BD133U (MBM temps are on-die) and Abit KT7. Arctic Silver grease was used in all tests. CPU Case Temp is the temp at that point where the CPU contacts the heatsink.


CPU Case Temp

Ambient Temp



MBM Temp

T-Bird @ 1400/Iwill KK266, 40 cfm (72 watts)

41.7 C

22.7 C



36 C

T-Bird @ 1400/Iwill KK266, 44 cfm (72 watts)

38.1 C

22.8 C



33 C

Duron @ 1000/Abit KT7, 40 cfm (63 watts)

39.7 C

22.8 C



37 C

Duron @ 1000/Abit KT7, 44 cfm (63 watts)

37.8 C

22.6 C



35 C

PIII @ 966/Iwill BD133u, 40 cfm (24 watts)

29.4 C

22.0 C



36 C

PIII @ 966/Iwill BD133u, 44 cfm (24 watts)

28.7 C

22.2 C



35 C

Delta = CPU temp – Ambient Temp
C/W = Delta / CPU Watts

Interpreting C/W: For every watt the CPU radiates, the heatsink will cool the core by the (C/W x watts) plus ambient temp. For example, at an ambient temp of 25 C, a C/W of 0.25 with a CPU radiating 50 watts means that the CPU temp will be 50 x 0.25 = 12.5 C over ambient temp, or 37.5 C. The lower the C/W, the better.

While the 44 cfm Delta turns in better C/Ws, whether the increase is worth substantially more noise is up to each consumer to decide. I think the Delta 38/clones are intolerable (as do many who toss them shortly after using them), so purchasing the Delta 44 cfm unit is without at least a rheostat is not recommended (IMHO).


The Dynatron turns in some nice C/Ws – high fan noise is the dominant issue that purchasers should consider. If you can live with it, it’s not a bad price/performance buy.

Email Joe

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