Supermicro X12SPA-TF 64L

The Supermicro X12SPA-TF 64L is a high-end workstation motherboard for Intel's Xeon W 3300 processor line. The primary focus of this processor series, and this motherboard, is to support a wide range of PCI-Express cards - but without needing to use PLX chips. This allows for a full four PCI-E x16 slots without the risk of stability issues that sometimes accompany PCI-E switches, although one of the slots shares lanes with M.2 drive connectors. This particular line of Xeons also offers eight-channel memory, allowing this board to support up to sixteen memory modules and 1TB of ECC RAM.

In addition to the massive number of PCI-Express slots, this motherboard also features a rare networking configuration: both 1Gb and 10Gb Ethernet ports, plus a third Ethernet for remote management. A lot of other connectivity is included as well: two USB 2.0, four USB 3.2 Gen 1, and two USB 3.2 Gen 2 ports (one of which is Type C) are present on the back panel, along with analog and digital audio plugs. Internally, eight SATA 6Gbps ports are available for drives along with a four M.2 connectors for high-speed NVMe drives - but using any of those does disable the last PCI-E x16 slot, as they share the same lanes.