NJAAKK-N911 vs NJAAKK-0006 vs LMTQF022-SD-R: Which DGX Spark Cable Do You Actually Need?

Several Part Numbers, One Cable Specification

If you are shopping for a cable to connect two NVIDIA DGX Spark systems, you will run into part numbers that look unrelated — NJAAKK-N911, NJAAKK-0006, LMTQF022-SD-R, and compatible-market spellings like NJAAKKR-0006. They are not several different products. They are one specification — QSFP112 passive direct-attach copper — across two manufacturers and two lengths. All are also marketed under the shorthand QSFP/CX7 cable.

This is the most common point of confusion on this cable, and buying on the part number alone rather than the length is how people end up returning one.

Part Number Decoder

This is the table to bookmark. Length is the differentiator:

Compatible Builds vs OEM Parts

Alongside the genuine Amphenol and Luxshare parts, the market carries compatible QSFP112 passive DACs, often under lightly modified spellings of the same numbers — NJAAKKR-0006 is one you will see. From a reputable source these meet the same electrical specification and work normally in DGX Spark and GB10 systems. They are still not the OEM part, and any seller who blurs that line is one to be careful with.

There is a second wrinkle worth knowing: compatible suppliers frequently apply the N911 family number to a 0.5 m cable, even though Amphenol's own N911 is the 400 mm part. That is why two listings can both say NJAAKK-N911 and arrive at different lengths. Check the stated length before you order.

The Manufacturers

Amphenol — NJAAKK-N911 and NJAAKK-0006. Amphenol is a global leader in interconnect technology and one of the OEMs for NVIDIA DAC cables. NVIDIA's DGX Spark User Guide lists the NJAAKK-N911 as QSFP to QSFP112, 32AWG, 400 mm, LSZH — and identifies NJAAKK0006 as the 0.5 m version of the same cable.

Luxshare — LMTQF022-SD-R. Luxshare Precision is one of the world's largest cable and connector manufacturers. NVIDIA lists the LMTQF022-SD-R as a QSFP112 400G DAC, 400 mm, 30AWG — the same specification as the Amphenol part, with a slightly thicker conductor.

Are They Interchangeable?

Electrically, yes. All of them plug into the same ports, carry the same passive copper signalling, and are covered by NVIDIA's approved cable list. The practical differences are length and conductor gauge, and at these distances the gauge difference has no meaningful impact on performance or signal integrity.

Length is the one that can actually bite you. 400 mm versus 0.5 m is a 100 mm difference — irrelevant for two units sitting side by side, but worth checking if you are cabling through a rack shelf or around a bracket. If neither length reaches, the QSFP112 stacking cable isn't made longer; use the 200G MCP1650-V in 1 m or longer instead.

What Port Do These Cables Connect To?

All of them connect to the DGX Spark's ConnectX-7 QSFP ports — the two QSFP ports on the back of the unit. Per NVIDIA's documentation there is no separate "stacking port"; those same two ConnectX-7 QSFP ports are used both for connecting Sparks together and for standard Ethernet / RoCE networking, and each port is capped at up to 200 Gb/s. So while these are QSFP112 / 400G-rated cables, on a DGX Spark the link runs at 200 Gb/s.

Good to Know

• Three units connect directly. Two Sparks take one cable; three Sparks take three cables in a ring using both QSFP ports on every unit — still no switch. At four nodes a switch is the supported route; owners also run four as a switchless ring of four cables with a custom NCCL build, outside NVIDIA support.
• The same ConnectX-7 ports handle both the unit-to-unit connection and general Ethernet networking — there is no separate dedicated port.
• The same approved cables apply to the OEM GB10 systems (HP ZGX Nano AI Station, Dell Pro Max with GB10, ASUS Ascent GX10).
• These are passive copper cables — no transceivers, no power draw, no firmware.

Which Should You Buy?

For two DGX Sparks side by side, any of these part numbers works and you need exactly one cable. Resilient Tec stocks the 0.5 m NJAAKK-N911 at $154 — cross-referenced to the NJAAKK-0006 and LMTQF022-SD-R. If you do not need a QSFP112 part specifically, the 200G QSFP56 MCP1650-V00AE30 at $84 also works well in practice, since the Spark's ports run at 200 Gb/s either way — and it comes in longer lengths when 0.5 m won't reach: 1 m ($97), 1.5 m ($104), 2 m ($115) and 3 m ($145).

Further reading: DGX Spark interconnect reference — approved part numbers, real-world throughput, and what to buy at two, three and four or more nodes.

FAQ

What is the difference between NJAAKK-N911 and NJAAKK-0006?
Length. Both are Amphenol QSFP112 passive DAC cables that NVIDIA lists as approved for DGX Spark. The NJAAKK-N911 is 400 mm; the NJAAKK-0006 (also written NJAAKK0006) is the 0.5 m version of the same cable. Electrically they are identical.

Is the NJAAKK-N911 the same as the LMTQF022-SD-R?
Functionally, yes. Both are 400 mm QSFP112 passive DAC cables that NVIDIA lists as approved for connecting DGX Spark systems. Amphenol makes the NJAAKK-N911 (32AWG) and Luxshare makes the LMTQF022-SD-R (30AWG); the gauge difference has no meaningful impact at these lengths.

What is NJAAKKR-0006?
It is a compatible-market spelling for a 0.5 m QSFP112 passive DAC, rather than a genuine Amphenol or Luxshare OEM part. Compatible cables from a reputable source meet the same electrical specification and work normally in DGX Spark and GB10 systems. Note that compatible suppliers often apply the N911 family number to a 0.5 m cable, so check the stated length rather than relying on the part number.

How much does the DGX Spark stacking cable cost?
The 0.5 m QSFP112 cable is $154 at Resilient Tec, sold new with a lifetime warranty and free US shipping. The lower-cost MCP1650-V00AE30 200G QSFP56 DAC is $84, with 1–3 m versions from $97 to $145 (prices checked October 26, 2026).

Where can I buy the NJAAKK-0006, NJAAKK-N911 or LMTQF022-SD-R?
Directly from Resilient Tec, which ships from Knoxville, Tennessee with free standard shipping on all US orders and POs and net terms available: 0.5 m QSFP112 DAC — $154 at resilient-tec.com

Ready to Buy?

In stock and shipping from Knoxville, Tennessee. Free standard shipping on all US orders — no minimum, no weight limit. Same-day shipping before 5:00 pm ET. Lifetime warranty, backed by Resilient Tec. Prices checked October 26, 2026.

• MCP1650-V00AE30 — 200G QSFP56 DAC, 0.5 m — $84, our best-selling Spark-to-Spark link
• MCP1650-V — 200G QSFP56 DAC, longer lengths — 1 m $97 · 1.5 m $104 · 2 m $115 · 3 m $145
• NJAAKK-N911 — QSFP112 400G-rated DAC, 0.5 m — $154 $174, equivalent to the NVIDIA-listed NJAAKK-0006

Scaling to 3 or 4+ nodes, or mixing GB10 vendors? Send us your node count and hardware and we'll confirm exactly what to buy — including when a switch is the real answer.

You Might Also Need

• Can You Build a 4-Node DGX Spark Cluster Without a Switch? — switch vs. switchless ring at four nodes, and how to cable each
• Network switches — the supported route at four nodes and the only route past four; a 200GbE-capable managed switch, not a repurposed office switch
• QSFP-DD to QSFP56 breakout cables — the part that actually lets a switch talk to Spark-class ports at 4+ nodes
• Outgrowing desktop hardware? — how the same DAC-first approach scales up to rack-mounted DGX H100/H200 over NDR InfiniBand
• NVIDIA OSFP part-number crosswalk — for when the next step up is optics, not copper
• Cat8 and structured cabling for the rest of the rack