From the site:

"Power Consumption

The PCI Express specification limits slot power to 25 watts. The DNBFC_S12_PCIe is capable of consuming power significantly beyond that. In addition to the PCIe fingers, a separate HDD connector adds a second path for power. This product is shipped with adequate heatsinking to consume 75 watts, but airflow is required in the chassis to dissipate the heat. Contact the factory if you require high reliability, no-fan heatsinks."

That thing would need lots more cooling.