As a design to put into a 1U case that location for the CPU on the daughterboard above the motherboard is really problematic, because it leaves almost no headroom for a proper passive heatsink.
In a well engineered 1U server setup you want the motherboard to be as low to the bottom of the chassis as possible, then the CPU in its socket, and a big passive heatsink (either aluminum or skived copper) occupying almost all the rest of the vertical room inside the case. The server should be like a front to back wind tunnel where the 40mm fans are moving air through the CPU heatsink(s) without the need for separate fans on top of the CPUs themselves.
The fan unit on top of that is really problematic from a above-the-fan vertical clearance and airflow perspective.
Additionally the SODIMM slots are blocking a typical airflow path from the front edge of the motherboard towards the rear. More normally a server motherboard for 1U would not use laptop size RAM, but would use normal size DIMMs oriented in such a way that they're parallel to the path of airflow.
(disclosure: I used to work for a server manufacturer and was responsible for procuring components from Taiwanese vendors, and designing new generations of 1U single and dual socket boxes to custom specs)
It is advertised as a workstation board, so the lack of design considerations for a rack mounted chassis isn’t surprising. That said, with the power draw of the entire board a 2U chassis with a standard circular fan on the CPU and modest chassis airflow is likely to be sufficient.
Its clear that the COM express carrier wasn't initially designed for this application. SolidRun has simply gotten enough requests for help solving rack density questions that they put together an answer.
In a well engineered 1U server setup you want the motherboard to be as low to the bottom of the chassis as possible, then the CPU in its socket, and a big passive heatsink (either aluminum or skived copper) occupying almost all the rest of the vertical room inside the case. The server should be like a front to back wind tunnel where the 40mm fans are moving air through the CPU heatsink(s) without the need for separate fans on top of the CPUs themselves.
The fan unit on top of that is really problematic from a above-the-fan vertical clearance and airflow perspective.
Additionally the SODIMM slots are blocking a typical airflow path from the front edge of the motherboard towards the rear. More normally a server motherboard for 1U would not use laptop size RAM, but would use normal size DIMMs oriented in such a way that they're parallel to the path of airflow.
(disclosure: I used to work for a server manufacturer and was responsible for procuring components from Taiwanese vendors, and designing new generations of 1U single and dual socket boxes to custom specs)