Thermaltake TMG A2, AT2 Coolers

[Rob Williams]

Thermaltakes slogan for their TMG cooler lineup is "Quality Life Starts With Silence." We have been pleased with the cooling performance of their products in the past, but silence and good cooling ability are two difficult things to put together. Let's take a look at how well both the A2 CPU cooler and AT2 GPU cooler perform in our tests.

You can read the full review here and discuss it here!

[Rory Buszka]

A quick note -- I did stop the chipset fan while listening to the noise these coolers produced.

As a gas turbine technician (jet engine guy) I must take exception to the following statement:

Close fin spacing creates high airflow impedance, reducing low-airflow effectiveness

Knowing what I know about aero/fluid dynamics, I know that the closer your blades are together (and the more surface area they occupy) in a fan, the greater the volumetric efficiency of the device. Ever seen a turbo-fan or turbo-jet engine with 4 or 5 fan blades? If fan blades spaced far apart is somehow a good idea, then our jet engine designers have been getting it all wrong for a great many years. Closely spaced fan blades are a plus, not a minus. If you 'd like to test that theory, cut off half the blades and measure the resulting airflow change.

[madmat]

There's a difference between the moving stator in a turbine and the fixed horizontal fins of a HSF. You might take exception with his statement but it is nonetheless true. The higher the fin count and the higher the fin density the lower the flow due to resistance to air flow. A moving stator acts as a compressor by forcing air through the fins due to shear caused by the motion of the stator and forward motion of the motor through the air. The fins in a heatsink don't move and there is no forward motion to help force the air through them. Instead you have a motionless layer of metal with X fin density comprised of fins of Y thickness with air being forced through it by a fan (Z) with a a rating of so many mm of H20 displacement. It's still based on fluid dynamics only the heatsink is the baffle behind the compressor rather than the compressor itself.

Originally Posted by madmat

There's a difference between the moving stator in a turbine and the fixed horizontal fins of a HSF. You might take exception with his statement but it is nonetheless true. The higher the fin count and the higher the fin density the lower the flow due to resistance to air flow. A moving stator acts as a compressor by forcing air through the fins due to shear caused by the motion of the stator and forward motion of the motor through the air. The fins in a heatsink don't move and there is no forward motion to help force the air through them. Instead you have a motionless layer of metal with X fin density comprised of fins of Y thickness with air being forced through it by a fan (Z) with a a rating of so many mm of H20 displacement. It's still based on fluid dynamics only the heatsink is the baffle behind the compressor rather than the compressor itself.

Actually my jet engine experience is on naval vessels used for propulsion and power generation, not in airplanes. Neither moves forward in a current of air, they sit in large boxes in the belly of a ship. If you think you're right then put it to the test.
I'll put up $20 that says I'm right.

[madmat]

I know I'm right. I'd hate taking your money...you probably work for the government so you need it worse than I do

The fact of the matter is when you stack thin plates in a high density it creates wind resistance and you have to have a higher velocity fan to overcome that resistance. This is why the Black Ice Pro series of radiators is tuned for low to medium flow fans and the Extreme series is tuned for high flow to a push-pull high flow fan config. It uses the same principal. The Black Ice Pro rads are thinner with a lower fin pitch or density. There are fewer fins per inch. The Black Ice Extreme is thicker with a higher fin pitch so it's got a denser fin count and offers way more resistance.

Yes, I know this is about air coolers but here's where I can show you I'm correct and that Rory was also correct. If you go to www.overclockers.com and read this article maybe you'll understand that pushing air through a high density object with a relatively low pressure fan isn't quite the same as moving air with a turbine.

[madmat]

So, I take it that you've seen the light...especially after reading about the flow chamber and seeing the testing done with the Swiftech heatsink where he concludes that the higher the fin count, the higher the wind resistance.