# Crucial Technology 4GB 288-Pin RDIMM DDR4 (PC4-21300) Memory Module, CL=19, Registered, 2666 MT/S Speed, ECC, 1.2V, 512Meg x 72, Single Ranked, x8 Based

- Category: RAM
- Brand: Crucial
- Model: CT4G4RFS8266
- Part number: CT4G4RFS8266
- Price (US): $37.70
- Price last checked: 2026-08-06
- Rating: 5.0/5 from 5 Amazon reviews
- Warranty: Limited Lifetime
- Product page: https://buildmypc.net/component-details/ram/crucial-ct4g4rfs8266/

## Specifications

| Spec | Value |
| --- | --- |
| Brand | Crucial |
| Model | CT4G4RFS8266 |
| RAM Size | 4 GB |
| Quantity | 1 x 4 GB |
| RAM Speed | DDR4 / 2666 MHz |
| DIMM Type | 288-Pin |
| CAS Lantency | CL19 |

## Key Features

- Crucial technology 4GB 288-pin RDIMM DDR4 (PC4-21300) Memory module - Crucial technology lifetime limited warranty
- Form Factor: RDIMM
- Total capacity: 4GB
- Ecc: ECC
- Module Type: DDR4 PC4-21300

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