Replacement for KD421SR4G: Drop-In Alternatives We Stock
Looking for a replacement for the KD421SR4G (KD421SR4G - Kingston 4GB DDR4-2133MHz PC4-17000 ECC Registered CL15 288-Pin DIMM 1.2V Single Rank x8 Memory Module w/TS)? Pro Disk Network ships Kingston 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 KD421SR4G
| SKU | KD421SR4G |
|---|---|
| Product | KD421SR4G - Kingston 4GB DDR4-2133MHz PC4-17000 ECC Registered CL15 288-Pin DIMM 1.2V Single Rank x8 Memory Module w/TS |
| Current price | $85.24 |
| Stock status | In Stock |
| Detail page | View KD421SR4G › |
Drop-in replacements for KD421SR4G
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.
Kingston Technology KVR21R15S8/4I 4GB DDR4-2133MHz PC4-17000 ECC Registered CL15 288-Pin DIMM 1.2V Single Rank Memory Module
SKU: KVR21R15S8-4I
Price: $85.24
Kingston Technology KVR21R15S8/4 4GB DDR4-2133MHz PC4-17000 ECC Registered CL15 288-Pin DIMM 1.2V Single Rank Memory Module
SKU: KVR21R15S8-4
Price: $85.24
Kingston Technology KVR21R15S8K4/16 16GB Kit (4 X 4GB) DDR4-2133MHz PC4-17000 ECC Registered CL15 288-Pin DIMM 1.2V Single Rank Memory
SKU: KVR21R15S8K4-16
Price: $315.37
Kingston Technology KVR21R15S8K4/16I 16GB Kit (4 X 4GB) DDR4-2133MHz PC4-17000 ECC Registered CL15 288-Pin DIMM 1.2V Single Rank Memory
SKU: KVR21R15S8K4-16I
Price: $315.37
Kingston Technology KVR21R15S4/8I 8GB DDR4-2133MHz PC4-17000 ECC Registered CL15 288-Pin DIMM 1.2V Single Rank Memory Module
SKU: KVR21R15S4-8I
Price: $89.12
Kingston Technology KTL-TS421/8G 8GB DDR4-2133MHz PC4-17000 ECC Registered CL15 288-Pin DIMM 1.2V Memory Module
SKU: KTL-TS421-8G
Price: $89.12
Kingston Technology KVR21R15S4/8HA 8GB DDR4-2133MHz PC4-17000 ECC Registered CL15 288-Pin DIMM 1.2V Single Rank Memory Module
SKU: KVR21R15S4-8HA
Price: $89.12
Kingston Technology KTD-PE421/8G 8GB DDR4-2133MHz PC4-17000 ECC Registered CL15 288-Pin DIMM 1.2V Single Rank Memory Module
SKU: KTD-PE421-8G
Price: $89.12
Kingston Technology KTM-SX421/8G 8GB DDR4-2133MHz PC4-17000 ECC Registered CL15 288-Pin DIMM 1.2V Memory Module
SKU: KTM-SX421-8G
Price: $89.12
Kingston Technology KVR21R15S4/8 8GB DDR4-2133MHz PC4-17000 ECC Registered CL15 288-Pin DIMM 1.2V Single Rank Memory Module
SKU: KVR21R15S4-8
Price: $89.12
Kingston Technology KTH-PL421/8G 8GB DDR4-2133MHz PC4-17000 ECC Registered CL15 288-Pin DIMM 1.2V Memory Module
SKU: KTH-PL421-8G
Price: $89.12
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.