ASRock Rack
ASRock Rack RB1U4OCU_G4 PCIe4.0 x16 to 4 OCulink server accessory
Connects a PCIe 4.0 x16 slot to four OCulink ports, each running at x4 bandwidth
- TypeOther
- SpecificationsDimensions: 1.24" x 4.23" (31.6mm x 107.5 mm) Upstream inter
- Connects four PCIe 4.0 x4 OCulink devices from one x16 slot
- Compact 31.6 mm by 107.5 mm form factor fits dense servers
- PCIe 4.0 x16 upstream delivers full bandwidth to every port
- Enables high-speed storage or GPU expansion in 1U chassis
- Brand-new server accessory ready for immediate deployment
Server Riser Card for 1U Chassis
The ASRock Rack RB1U4OCU_G4 is a server accessory that converts a single PCIe 4.0 x16 slot into four OCulink connectors. It is designed for administrators who need to add multiple high-speed links inside a compact 1U system.
Suited for dense storage or accelerator deployments
This card fits builders who want to connect up to four PCIe 4.0 x4 devices through OCulink cables. It is not for systems that lack a full x16 electrical slot, for chassis taller than 1U where a different bracket may be needed, or for installations requiring a different external connector type.
PCIe 4.0 x16 upstream with four OCulink ports
The upstream interface runs at PCIe 4.0 x16 and splits into four external OCulink connectors, each operating at PCIe 4.0 x4. This lane allocation is the key specification that determines whether the card matches your backplane or drive enclosure.
Highlights
- Connects four PCIe 4.0 x4 OCulink devices from one x16 slot
- Compact 31.6 mm by 107.5 mm form factor fits dense servers
- PCIe 4.0 x16 upstream delivers full bandwidth to every port
- Enables high-speed storage or GPU expansion in 1U chassis
- Brand-new server accessory ready for immediate deployment
Specifications
| Brand | ASRock Rack |
|---|---|
| Model | RB1U4OCU_G4 |
| Type | Other |
| Specifications | Dimensions: 1.24" x 4.23" (31.6mm x 107.5 mm) Upstream interface: PCIe4.0 x16 External: 4 OCulink (PCIe4.0 x4) |
| Shipping weight | 0.16 kg |
| Package size | 222 × 140 × 51 mm |
Questions about this item
Does my server chassis have a PCIe 4.0 x16 slot free for the RB1U4OCU_G4 riser?
The card needs a single PCIe 4.0 x16 slot on the motherboard; without that upstream link the four OCulink ports cannot function.
Will the four OCulink ports run at PCIe 4.0 x4 speeds if my CPU only supports PCIe 3.0?
The riser passes through the upstream speed, so a PCIe 3.0 host limits each OCulink link to 3.0 x4 bandwidth.
How can I confirm each OCulink port is negotiating PCIe 4.0 x4 after installation?
Check the operating system or BIOS device list — every attached drive or adapter should show a 4.0 x4 link width and speed.
New to this? Buying server hardware with crypto — what to check, what it costs to pay, and what is never asked for.
Also in this aisle
People compared these
Same shelf, same checkout — eight coins and a 30-minute rate lock.



