i was thinking about 180° of you solution, but because gravity force and fluids in the pipes ...
In you solution at the moment there liquid in heatpipes changing they aggregate state to gas on contact surfaces, what are on the top. You bacame a bubbles, and new luquid has problem to became a contact direct to hottest surfaces.
My solution where better, so the steam bubbles will go up like in a pan with water on the kitchen stove
something like this from Genesis mining farm in Island
I think your setting is good. You can confirm it by chaning the direction of the cards and see the temperature difference.
I have another question, whats is the best solution for cooling down room
because of mining PC room gets hot
I tried alot of solutions of fans they all failed , some of them even make the temp. go higher , the only solution which dropped down the temp immediatly is the ventillation , your mining room should have a very good ventillation of the hot air constantly.