NEC part number MCX4121A-XCAT identifies the MCX4121A-XCAT - Mellanox ConnectX-4 10Gigabit Ethernet Card, an enterprise-grade Networking Devices unit appropriate for data-center, server-room, and workstation deployment. The component is intended for use in enterprise rack server and data-center deployments where matched-pair installation, hot-spare provisioning, or matched-lot procurement is required. Technical specifications include network speed of 10 GbE. Typical use cases include enterprise LAN core-distribution-access architecture, hyperconverged cluster east-west traffic, SAN fabric uplinks, and replacement of EOL/EOSL networking infrastructure under existing OEM warranty contracts. Pro Disk Network maintains the MCX4121A-XCAT in our enterprise inventory and verifies each unit against manufacturer datasheet specifications prior to listing. New stock ships factory-sealed where available; refurbished units are tested under load before dispatch and ship with a 30-day Pro Disk Network functional warranty. Net 30 terms are available for qualified business accounts. Same-day dispatch on in-stock orders placed before 3pm ET; free standard ground shipping on US orders over $150.
The MCX4121A-XCAT is a NEC networking devices component with network speed 10 GbE. Pro Disk Network sells the MCX4121A-XCAT for $140.00 with same-day US shipping and a 30-day free return guarantee.
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Reviewed by:Pro Disk Network Engineering Team — . Specifications, compatibility, and pricing for the MCX4121A-XCAT verified against the manufacturer datasheet and our internal lab benchmarks.
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Florida-Registered LLC — 7345 W Sand Lake Rd, Orlando FL 32819
Same-Day US Shipping — orders before 3pm ET ship today via FedEx/UPS
30-Day Free Returns — pre-paid label included on all US orders
Net 30 Available — for verified business buyers
2,000+ B2B Customers — MSPs, government, education, enterprise IT
Quick Answer: Is the MCX4121A-XCAT compatible with my switch?
Pro Disk Network validates every MCX4121A-XCAT against the target switch's published compatibility matrix before shipment. If you let us know your switch model and firmware version, we will confirm fitment and code the module appropriately (Cisco-coded, Juniper-coded, HPE-coded, etc.) at no extra charge.
How fast does the MCX4121A-XCAT ship?
If in stock, the MCX4121A-XCAT ships same business day on US orders placed before 2 pm ET. Most US ZIP codes receive next-business-day or 2-day delivery via FedEx/UPS Ground or Express. Bulk and project orders shipping in pallets are typically dispatched within 24-48 hours.
The MCX4121A-XCAT is deployed by US enterprises, MSPs, government, and education customers across multiple infrastructure scenarios. Below are the most common deployment patterns Pro Disk Network sees in real-world orders.
Spine-Leaf Fabric — Top-of-rack 25G/100G aggregation between leaf and spine switches. Match speed and form factor across both endpoints.
Server Uplink — 10G/25G server-to-leaf uplink — pair with matching DAC or AOC at the host NIC to avoid optic mismatch.
DCI (Data Center Interconnect) — Inter-DC routing or aggregation. LR4/LR8 transceivers for 10–80 km, ER4 for 40 km, ZR4 for coherent long-haul.
Campus Distribution — Catalyst-class campus distribution between IDF and MDF closets. PoE+ where wireless APs and IP phones share infrastructure.
New, Bulk, or Refurbished — Choosing Your Tier
Pro Disk Network offers the MCX4121A-XCAT across three procurement tiers. Each tier is fully functional and warranted; the choice comes down to budget, warranty length, and whether the deployment is production-critical or capacity-expansion.
Tier
Discount vs OEM List
Warranty
Best For
New (Sealed OEM)
25–40%
NEC manufacturer warranty (1–5 yr)
Production-critical first-tier
New (Bulk OEM)
50–65%
3-year Pro Disk Network warranty
New cluster builds, secondary tier
Refurbished
75–85%
12-month advance replacement
Capacity expansion, lab, dev/test, EOL refresh
Bulk & Volume Pricing for MCX4121A-XCAT
Ships from our Orlando, FL warehouse — same-day US dispatch on orders placed before 2pm ET. Net 30 terms available for verified businesses, government and education.
Volume discounts on the MCX4121A-XCAT are automatic at checkout. Net 30 terms available for verified businesses, government, and education. Email sales@prodisknetwork.com for orders above 100 units.
Quantity
Discount
Unit Price
1
0%
$140.00
5+
4%
$134.40
10+
8%
$128.80
25+
13%
$121.80
50+
18%
$114.80
100+
23%
$107.80
What is the MCX4121A-XCAT?
The MCX4121A-XCAT is a NEC enterprise networking device with network speed 10 GbE, manufactured by NEC. Pro Disk Network ships this part new and certified-refurbished from our US warehouse with same-day dispatch on orders placed before 3 PM ET, backed by a 30-day return guarantee.
Pros & Cons of MCX4121A-XCAT
Pros
Lower cost than the OEM channel — same physical optic
RoHS, FCC, and CE compliance documentation available
SFP+/QSFP28 modules pre-coded for major vendor firmware
Cons
DAC cables capped at 7 m — use AOC or fibre for longer runs
SR optic vs LR optic confusion — verify before ordering
Refurbished tier optic does not include retail vendor packaging
Frequently Asked Questions about MCX4121A-XCAT
Is the MCX4121A-XCAT a genuine NEC part?
Yes. Pro Disk Network sources every MCX4121A-XCAT as factory-original NEC inventory verified against the manufacturer parts registry before listing. New units arrive sealed in OEM packaging; refurbished units are pulled from decommissioned NEC servers, surface-tested, and re-warranted by Pro Disk Network for 12 months.
Is the MCX4121A-XCAT compatible with my switch?
Pro Disk Network validates every MCX4121A-XCAT against the target switch's published compatibility matrix before shipment. If you let us know your switch model and firmware version, we will confirm fitment and code the module appropriately (Cisco-coded, Juniper-coded, HPE-coded, etc.) at no extra charge.
How fast does the MCX4121A-XCAT ship?
If in stock, the MCX4121A-XCAT ships same business day on US orders placed before 2 pm ET. Most US ZIP codes receive next-business-day or 2-day delivery via FedEx/UPS Ground or Express. Bulk and project orders shipping in pallets are typically dispatched within 24-48 hours.
What is the warranty on the MCX4121A-XCAT?
New MCX4121A-XCAT units carry the full NEC manufacturer warranty (typically 1 to 5 years depending on product line). Refurbished and bulk-OEM units include a Pro Disk Network advance-replacement warranty (12 months refurbished, 36 months new bulk). DOA replacement is free within 30 days of receipt.
Do you offer bulk pricing for the MCX4121A-XCAT?
Yes. Pro Disk Network offers automatic volume discounts at 10, 25, 50, and 100+ unit tiers. Net 30 terms are available for verified businesses, government, and education buyers. Email sales@prodisknetwork.com with the quantity and target ship date for a quote within one business day.
Pro Disk Network Buyer’s Guide: Networking Devices
Optic Coding, Vendor Lock-In, and Multi-Vendor Compatibility
Networking optics — SFP, SFP+, QSFP+, QSFP28 — are physically interoperable across vendors but logically restricted by firmware coding. The MCX4121A-XCAT is coded for a specific vendor family at our factory step before shipping, which preserves the OEM warranty workflow and allows the optic to be recognised without ‘service unsupported-transceiver’ CLI overrides. Mixing third-party optics with same-vendor optics in the same chassis is safe; mixing across vendor codings sometimes triggers warnings in the switch log.
Bandwidth Sizing for Spine-Leaf, EVPN-VXLAN, and Hyperconverged Storage
For EVPN-VXLAN overlays, the MCX4121A-XCAT carries the underlay tunnels in addition to the workload traffic. Plan for VXLAN encapsulation overhead (50 bytes) plus MTU headroom; set the underlay MTU to 9216 (jumbo frames) and the overlay MTU to 9000. Make sure both the MCX4121A-XCAT and the connected NICs support jumbo frames — some older NICs cap at 9000-byte payloads even when jumbo-enabled.