Quote from: Sophokles on July 02, 2013, 09:24:45 PM

Quote from: SebastianJu on July 02, 2013, 03:27:04 PM

Quote from: oktar on July 02, 2013, 12:33:09 PM

Quote from: SebastianJu on July 02, 2013, 12:05:43 PM

Wow, didnt know that its so featurerich... and all 4! power connectors are for cables that goes horizontal right? The left 3 for sure but im not sure with the right one. But i guess the second right one would be the one to use with a ATX-PSU.

Do you mean the green power connector goes with ATX? I wonder how to split power from ATX to multiple boards, like 14? What additional cables/connectors do we need?

No, the connector on the left side of the green connector. Im not sure what the green connectors cable would look like.
You would most probably split the power from a psu via y-cables.

Quote from: bigbeninlondon on July 02, 2013, 01:07:22 PM

Quote from: SebastianJu on July 02, 2013, 12:05:43 PM

Quote from: Sophokles on July 01, 2013, 09:56:13 PM

Putting a heat sink on top will restrict the airflow over the pcb. The pcb has internal copper layers ('ground' is usually designed as a plane) which act as heat spreaders as well.

Do you say the other side of the pcb needs airflow too? I intended to force the airflow from the fans through the heatsinks only to maximize cooling. Do i have to rethink this?

The chips are designed to release heat out of the bottom, and putting a heatsink on the top of the chips can restrict convection and cause the chips to overheat. The top of the board doesn't need additional air flow AFAIK. The fan on the heatsink should create enough airflow around the board that all you need on top is convection for the other parts. That is, don't cover it up, but no need for anything else.

So it doesnt need airflow but then you say the fan will make enough air. But what will happen when i force the airflow ONLY through the heatsink. You know like creating a tunnel. I would like to take 2 miners with heatsink and put them together tight with the heatsinks. Then put a fan on the side and somehow build a tunnel that only allows the air flowing between the ribs of the heatsinks. Im not sure yet what material would be best for this but i think it would greatly effect the cooling because i think otherwise most of the air is going useless the easier way.
So would that be possible or is it needed to put a little bit of the airflow to flow above the other sides of the boards.

The avalon chips will certainly be ok with bottom cooling only, even if the top side is completely insulated. They are designed to release the heat via the bottom. But there might be other components on the board, which might need a slight breeze, to prevent them from getting quite hot (voltage regulators for example).

Actually I think people were warned to specifically not insulate the top of the chip. I can't remember where, but I distinctly remember reading that a heatsink on top of the chip can actually cause damage. Maybe that was because the pressure of the heatsink can cause chips to come loose from the board or something, but I do remember being warned not to try to exhaust heat out of the top.