Noctua NH-D12L Dual Tower CPU Cooler - 120mm-Class Cooling For 4U Server Cases

For the Noctua NH-D12L testing I was using an Intel Core i9 12900K "Alder Lake" system for testing. This Core i9 12900K system was running within a Rosewill RSV-L4500 4U rackmount chassis. Up to this point the Core i9 12900K was being cooled by a Noctua NH-U9S with a dual fan configuration due to 4U height requirements not allowing a larger heatsink/fan.

Sure enough the Noctua NH-D12L installed fine within the Rosewill 4U chassis with just enough room to close the lid. When installing a second 120mm Noctua fan there was some concern around spacing with the ASUS ROG STRIX Z690-E motherboard due to not enough clearance at the back of the heatsink to fit the second fan but there ended up being just enough clearance at the front when positioned immediately above the DDR5 memory modules. This did offset the front fan slightly due to the DDR5 module height but still provided just enough clearance to be able to close the lid on the 4U server case.

For getting an idea of the thermal performance with the Noctua NH-D12L within the 4U chassis, the configurations tested included:

Noctua NH-U9S 2-Fans Auto - The prior configuration of this Core i9 12900K Alder Lake Linux system with the cooler using two fans and in the default auto PWM mode.

Noctua NH-U9S 1-Fan Auto - Dropping the NH-U9S configuration back to its single fan configuration and with auto PWM default.

Noctua NH-D12L 1-Fan Auto - The stock configuration of this new 4U-friendly Noctua heatsink.

Noctua NH-D12L 2-Fans Auto - Adding a second 120mm fan to the NH-D12L.

Noctua NH-D12L 2-Fans Full - Rather than using the auto PWM mode, switching over to the full/100% speed configuration for both of these CPU heatsink fans.

No other changes were made to the system during testing besides the above mentioned heatsink/fan swaps. Working with the Noctua NH-D12L was easy with this 4U enclosure. During operation the Noctua NF-A12x25r fans were certainly quiet in their PWN mode and nothing to raise complaints about -- even at full-speed they weren't too noisy either and still below normal for most 2U/4U cooling setups for high performance desktops/servers.