CalDigit RAID Card - Manual (Page 55)

55 C. Wintel PC
3.6 Install PCI-Express screws back in place.
3.7 Insert the side panel and close the latch
Reconnect the external cables and the power cord. Turn on the power of
your PC.
Note: To insure proper airflow (and avoid over heating), make
sure that the fan module is running correctly and the side panel is
completely closed. Place your hand near front of the Mac Pro and
make sure that you can feel air moving.