Replacement for 517721-B21: Drop-In Alternatives We Stock
Looking for a replacement for the 517721-B21 (HP 517721-B21 2 x Ports 40Gb/s PCI Express 2.0 Host Bus Adapter)? Pro Disk Network ships HP drop-in replacements and equivalent modern parts from US inventory. Every alternate below is in-stock today with same-day shipping for orders placed before 2pm ET. If your unit is still under warranty, contact our engineering team — we offer cross-shipping for B2B customers on Net 30 terms.
About the 517721-B21
| SKU | 517721-B21 |
|---|---|
| Product | HP 517721-B21 2 x Ports 40Gb/s PCI Express 2.0 Host Bus Adapter |
| Current price | $205.26 |
| Stock status | In Stock |
| Detail page | View 517721-B21 › |
Drop-in replacements for 517721-B21
Each part below is currently in our US warehouse, ships same-day for orders before 2pm ET, and includes our 90-day warranty. SKUs link to the full product page with photos, datasheets and B2B quote form.
HPE 013252-001 SC44GE SAS 1 x Ports Internal + 1 x Port External PCI Express x8 Host Bus Adapter for ProLiant DL120 G5 Sever
SKU: 013252-001
Price: $145.26
HP 661687-001 InfiniBand 2 x Ports 40Gb/s 544FLR-QSFP PCI Express 3.0 x8 Host Channel Adapter for ProLiant Gen8 Servers
SKU: 661687-001
Price: $71.58
463051R-001 - HP PCI-X Adapter 64-Bit 133MHz 1-Channel Ultra320 SCSI Controller (HBA) Host Bus Adapter
SKU: 463051R-001
Price: $646.83
HPE R8N87A#ABA Aruba 6000 24G-Class4-PoE-4SFP 24-Ports 10/100/1000Base-T PoE 4-Ports SFP 1-Ports USB-C Console 1-Ports USB Type-A Host Layer 2 Managed 1U Rack-mountable Gigabit Ethernet Network Switch
SKU: R8N87A#ABA
Price: $1,109.16
HPE R8N87-61001 Aruba 6000 24G-Class4-PoE-4SFP 24-Ports 10/100/1000Base-T PoE 4-Ports SFP 1-Ports USB-C Console 1-Ports USB Type-A Host Layer 2 Managed 1U Rack-mountable Gigabit Ethernet Network Switc
SKU: R8N87-61001
Price: $1,342.11
HPE R8N87-61101 Aruba 6000 Series 24G-Class4-PoE-4SFP 24-Ports 10/100/1000Base-T PoE + 4-Ports SFP + 1-Ports USB-C Console + 1-Ports USB Type-A Host Layer 2 Managed 1U Rack-mountable Gigabit Ethernet
SKU: R8N87-61101
Price: $1,342.11
718201-001 - HP LPE1605 Dual-Port Fibre Channel 16GB/s PCI-Express Mezzanine Host Bus Adapter
SKU: 718201-001
Price: $47.37
718577-001 - HP LPE1605 Dual-Port Fibre Channel 16GB/s PCI-Express Mezzanine Host Bus Adapter
SKU: 718577-001
Price: $47.37
SN1100E-2P - HP Dual-Port Fibre Channel 16Gb/s PCI Express 3.0 Host Bus Adapter with Standard Bracket
SKU: SN1100E-2P
Price: $57.89
726907-B21 - HP H240 12GB Dual Port PCI-Express 3.0 X8 Smart Host Bus Adapter
SKU: 726907-B21
Price: $61.05
How we pick replacements
Every recommendation above was selected using these criteria:
- Drop-in compatibility — same form factor (2.5"/3.5", PCIe slot, SFP port, etc.), so it fits the original chassis without modification
- Equivalent or better performance — matched on RPM/IOPS/speed/throughput, never downgraded
- Same-brand-preferred — we list the OEM-equivalent first when available, then trusted aftermarket
- Warranty coverage — 90-day Pro Disk warranty on every part, with 1-year option for B2B
- In stock today — never recommend a part that is on backorder
Need help confirming compatibility?
Our engineers validate every replacement against your specific server, switch, or chassis model before shipment. Email sales@prodisknetwork.com with your platform model (e.g., Dell PowerEdge R740, HP DL380 Gen10, Cisco Catalyst 9300) and we will confirm the exact part number that drops into your hardware.