I am super interested in this! Can you upload some pictures how did you fix the bifurcated riser and how it is linked to the pcieX riser!?? Thanks a lot!
5cm riser finally arrived, so I could finish the build. Here's pics as promised. First the riser components:
Routing 2 fan cables from front to 4X fan hub. Cutting the Dan A4 plastic separator to shield the riser backside.
Routing 4 fans to the fan hub, placed below the 10GBs ethernet card. Riser and bifurcation card in place.
Plugging in the 10GBs Asus ethernet card on top of the fan hub, removing small back panel to make route for ethernet cable.
Completed and running. Just panels removed to show the internals. Running GPU and 10GBs ethernet from the bifurcated x16 PCIE.
Perfect
I got a bit lucky with the build. Everything lined up perfectly in the end, including the route for ethernet cable input, cutting the DAN a4 separator plastic to shield the riser backside, fitting the riser and ethernet card tighly.
The completed build runs delidded i9-7980XE with liquid metal and copper plate, with Asetek 545LC, and 4 extra case fans. So the 18 cores run 36 threads@3.4 GHz stable without thermal throttling. 64GB quad-channel memory, 2TB Evo 970 SSD. With the 10GBs connection this DAN A4 is used as a portable coprocessor for computation-heavy workloads.