The NEC MCX4121A-ACAT (MCX4121A-ACAT - Mellanox ConnectX Single Port PCI-Express 100 Gigabit Server SFP Ethernet Adapter Network Interface Card) is a Networking Devices component engineered for sustained enterprise-class workloads. Manufactured to OEM specifications and tested for compatibility with enterprise rack server and data-center deployments, this part addresses common procurement scenarios where exact-match replacement, capacity expansion, or new-build deployment is required. Technical specifications include network speed of 100 GbE. Common deployment scenarios include data-center ToR (top-of-rack) switching, server-to-storage NAS/SAN connectivity, 10/25/40/100 GbE backbone aggregation, and edge router replacement in branch-office deployments. Pro Disk Network sources the MCX4121A-ACAT through authorised distribution channels and applies a verification check against the OEM compatibility matrix before each unit is added to active inventory. Each unit ships from a US fulfillment hub (Hillsboro OR, Atlanta GA, or Phoenix AZ) with same-day dispatch on in-stock orders before 3pm ET. Net 30 / Net 60 terms available for qualified business, government, and education accounts. 30-day Pro Disk Network functional warranty included; free US ground shipping on orders over $150.
The MCX4121A-ACAT is a NEC networking devices component with network speed 100 GbE. Pro Disk Network sells the MCX4121A-ACAT for $280.00 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-ACAT 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-ACAT compatible with my switch?
Pro Disk Network validates every MCX4121A-ACAT 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-ACAT ship?
If in stock, the MCX4121A-ACAT 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-ACAT 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-ACAT 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-ACAT
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-ACAT 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%
$280.00
5+
4%
$268.80
10+
8%
$257.60
25+
13%
$243.60
50+
18%
$229.60
100+
23%
$215.60
What is the MCX4121A-ACAT?
The MCX4121A-ACAT is a NEC enterprise networking device with network speed 100 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-ACAT
Pros
Drop-in replacement for failed line cards or transceivers
Bulk-pack pricing for multi-rack deployments
Coding to OEM TLV is verified before shipping
Cons
Third-party optic — some firmware revs require "service unsupported transceiver-type"
Bulk DAC orders may ship LTL on >100-pc reels
Confirm transceiver coding before mixing vendors in the same chassis
Frequently Asked Questions about MCX4121A-ACAT
Is the MCX4121A-ACAT a genuine NEC part?
Yes. Pro Disk Network sources every MCX4121A-ACAT 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-ACAT compatible with my switch?
Pro Disk Network validates every MCX4121A-ACAT 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-ACAT ship?
If in stock, the MCX4121A-ACAT 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-ACAT?
New MCX4121A-ACAT 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-ACAT?
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-ACAT 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-ACAT 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-ACAT and the connected NICs support jumbo frames — some older NICs cap at 9000-byte payloads even when jumbo-enabled.