Lenovo 4XH7A61081 Thinksystem SR650 V2/SR665 X16/X16/E PCIE G4 Riser 1/2 Optio

Lenovo 4XH7A61081 ThinkSystem PCIe Gen4 Riser Card

Overview

The Lenovo 4XH7A61081 is a PCIe Gen 4 riser card designed to expand GPU, storage controller, or high-bandwidth NIC capacity in ThinkSystem rack servers. This X16/X16/E configuration supports two full-length x16 PCIe slots plus one additional edge slot, giving integrators the flexibility to add compute accelerators or multi-port network adapters without compromising primary slot availability. The 4XH7A61081 is positioned as Riser 1/2 Option — meaning it slots into the standard riser 1 or riser 2 bays of compatible ThinkSystem platforms, making it a direct path to expanding I/O density on already-deployed servers.

Compatibility

Verified compatible with the following Lenovo ThinkSystem platforms:

• ThinkSystem SR650 V2 — 2U dual-socket server; this riser fits the standard rear riser cage positions
• ThinkSystem SR665 — 2U AMD EPYC-based server; same riser bay form factor

Confirm the target server's riser cage configuration and firmware revision before ordering — some SR650 V2 and SR665 builds ship with alternate riser kits pre-installed that may require removal before this card can seat. Consult the server's server components documentation or the Lenovo ThinkSystem catalog for riser cage compatibility matrices by chassis revision.

Installation Notes

Physical dimensions are 13.80 x 9.10 x 6.40 in and the card weighs 1.75 lb — factor this into rack density planning if the server is near its internal weight limit. The PCIe Gen 4 interface requires a Gen 4-capable CPU and platform to deliver full bandwidth; installing in a Gen 3 slot will work electrically but will halve per-lane throughput, which matters for high-bandwidth accelerators. Ensure the target chassis has an available riser cage bracket and that the power delivery configuration supports the add-in cards you plan to install in the expanded slots. No special tooling is specified beyond standard server servicing equipment.