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.

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”:

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.

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!

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

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.

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.

NOTE THAT YOU MUST USE A 3-4 PIN CONVERTER!

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.

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