Supermicro PERIPHERAL, RSC-R1UU-E8PR Motherboard Slot Type - UIO Slot (X8DTU/-F, X7DWU, X7DCU); Riser Card Output Slot(s) - 1 PCI-E x8. $43.54 $24.19
Supermicro PERIPHERAL, RSC-R1UU-E8R+ REV 1.00, PBF Motherboard Slot Type - UIO Slot; Riser Card Output Slot(s) - 1 PCI-E x4/8. $39.92 $22.18
Supermicro PERIPHERAL, RSC-R2U-2E8 RSC-R2U-2E8, signal 2x PCI-E x8 2.0, output 2x PCI-E x8 2.0, 2U, LHS $99.76 $55.42
Supermicro PERIPHERAL, RSC-W2-66 LHS, Passive, Output: (2) PCI-E x16 Signal: (2) PCI-E x16 $120.47 $66.93