Roy, contrary to what the other guy said, that is a perfectly logical
supplement to the OE cooling system. ANYTHING that reduces the pressure
at the exit venting will improve airflow over the heatsink.
Increase inlet and exit free area and/or increase inlet pressure or
reduce outlet pressure..... all will increase flow volume.
Alternatively/additionally, the industrious owner might also consider a
custom duct in the back that would provide for adding multiple 120mm or
140mm high-quality fans set to blow air IN. I prefer Noctua fans these
days. They are quiet, come with anti-vibration mounts built in, and
there are full anti-vibe gaskets available on some models that prevent
flow short circuits. They also come in 3-pin or 4-pin models. 3-pin
models can generally be set to run at full speed or at 1 or 2 slower
speeds. The trick solution would be to use 4-wire fans and your own
feedback loop controller to adjust the speed dynamically..... albeit,
you need to test and modify any of the ready-built controllers to make
sure you aren't broadcasting RF birdies with the PWM.
The benefit to putting fans in back blowing through the stock
screen/fans is that you get the slight added benefit of over-pressuring
the chassis which tends to keep the chassis interior cleaner. Assuming
adequate rear spacing, you can hide the fans a bit more....
I could go on... I love thermal control stuff... I'd be interested to
see the numbers on how much power/heat is dissipated at 1500W key down...
73,
______________________
Clay Autery, KY5G
(318) 518-1389
On 05/21/18 14:32, Roy Koeppe wrote:
"Do the KPA1500 fans push air into the box? If so, why doesn't the
KPA500 fan do that. If the KPA1500 fans pull out of the box why would
it be appropriate to use an additional fan that opposes this airflow?"
Yes, they do...which is also opposite of airflow in K3s. The idea of
the additional fans is that they are much more quiet than the built
ins, even when they are on speed #1 . And they prevent the built ins
from running so much or not at all. Simpleminded, I admit.
Roy K6XK
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