Things have been busy, but I had some time over the weekend to get this partially up and running.
I'm leaving the PCIe cables just in case this chassis gets repurposed some day. The rest of the cables are stashed under the PSU.
Currently stress testing (mprime, y-cruncher, and stressapptest) on a minimal Arch install.
At stock clocks, CPU boosts to 4050MHz all-core while running mprime blend, with CPU fan set to "Standard" mode in BIOS. Looks like there is quite a bit of headroom on the CPU, so I will be OCing the CPU on the overkill router. Currently power usage is sitting at 85W at the wall while running mprime.
Both NICs detected and all ports are working with the PCIe slot set to x8 x8. Bifurcation options in the BIOS are x8 x8, x8 x4 x4, and x4 x4 x4 x4.
ECC UDIMMs booted right up at 3200MHz, and can be monitored for errors via rasdaemon. Totally unnecessary for a router, but I have a bunch of extra ECC UDIMMs, so into the router they go. No issues at 3200 with jedec timings, so it looks like I will also be OC'ing the RAM.
List of things still to complete:
Fab custom top panel with filtered cut-outs for cooler intake and intake above the NICs
Replace secondary 8-pin EPS with custom length 4-pin EPS for the bifurcation card
Fab/install power switch, power LED, and activity LED
Install and wire up remote power break-out board for PiKVM
Once I finish the rest of the build, then it will be on to testing VyOS.