Last year, I purchased a Supermicro X12SDV-4C-SP6F for a new NAS build. The motherboard has 10x SATA 3 ports, 2x M.2 interfaces, 2x 25G SFP ports, IPMI, and supports 256GB ECC DDR4 RAM, making it well suited to its use as a NAS.

The motherboard’s one major drawback is its suboptimal cooling. Sporting a minimal passive heatsink, its CPU idled at ~65ºC. While likely well below the Xeon D-1718T’s seemingly unpublished thermal limit, I’d like this number to come down quite a bit.

There was some discussion in the comments of ServeTheHome’s motherboard review about upgrading the cooling. Active cooling would be ideal, but no one had identified a cooler that would fit. One commenter mentioned the Supermicro SNK-C0111AP4L as a potential option.

I decided to try it out. I purchased a SNK-C0111AP4L from Wired Zone for $55 ($72 with shipping and tax). Once it arrived, I removed the existing heatsink and tried to install it.

I immediately hit a problem. The chokes next to the barcode sticker blocked the cooler from being screwed down.

CPU cooler blocked by motherboard chokes

Aluminum is no match for me. Using my dremel, I removed a ~.25” x 1” section of the heatsink.

Section of heatsink removed using dremel

The heatsink now fit like a glove.

Modified heatsink installed on motherboard

The CPU runs ~25ºC cooler at idle. The CPU fan is connected to FAN1 per the manual’s recommendation, though the fan is fairly loud. I’ve explored replacing the fan with a Noctua 40mm but the cooler’s screw holes are non-standard.

As a potential further upgrade, I’ve ordered a Supermicro SNK-P0070APS4. It sports a significantly larger heat sink and larger fan, which should result in a much cooler and quieter setup. It also appears to have a cutout that aligns with the motherboard’s chokes. Dimensions are available online for the SNK-C0111AP4L’s screw holes (69.2mm x 46mm) but not for the SNK-P0070APS4. I’m a bit doubtful it’ll fit given the LGA3647-0’s purported significant size, but I shall report back.