Today I upgraded the server to dual Intel Xeon X5650 hex core CPUs.  I was waiting on some actively cooled LGA1366 (Socket B) heat sinks, which I found for cheap on eBay, but they had to come from China.  For some reason, probably because they are old tech, the LGA1366 Xeon specific coolers are hard to find these days.  Noctua still makes a great unit, but it costs about $55 USD each.  Plenty of used Core i7 LGA1366 coolers with the pop-in mounts, but few for the Xeons with their screw-in mounts.  I wish Intel would stick with some kind of cooling mount standard for a long while.  That’s one area that AMD has them beat for sure.

The old L series CPUs were limited to 40W TDP and the passive heat sinks included with the motherboard worked fine, even under 100% CPU stress testing.