Crucial
Crucial RAM 8GB DDR4 2666 MHz CL19 Desktop Memory CT8G4DFRA266
Bottom line: The Crucial RAM 8GB DDR4 2666 MHz CL19 Desktop Memory CT8G4DFRA266 ($66.99 on Amazon as of 2026-10-06): Micron-owned brand with component- and module-level testing before shipping; main trade-off: 2666 MT/s sits at the low end of DDR4; enthusiast boards run 3200 and above.
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*Price sourced from Amazon.com. Last updated 2026-10-06. Price and availability subject to change.
Pros & Cons
Pros
- ✓ Micron-owned brand with component- and module-level testing before shipping
- ✓ Standard 288-pin non-ECC UDIMM fits any DDR4 2666 MT/s desktop board
- ✓ Crucial System Scanner and Advisor Tool verify board fit before you order
- ✓ Sold as a single 8GB stick, so you can fill one empty slot instead of a full kit
Cons
- ✗ 2666 MT/s sits at the low end of DDR4; enthusiast boards run 3200 and above
- ✗ CL19 is a loose timing; tighter CL16 modules exist at the same speed grade
- ✗ One stick alone gives no dual-channel bandwidth, you need a matched pair
- ✗ 8GB on its own is thin for current games and AI workloads
Manufacturer description
The Crucial CT8G4DFRA266 is an 8GB DDR4 UDIMM built for desktop systems that accept 2666 MT/s unbuffered memory. It runs CL19 latency on the industry-standard 288-pin DDR4 layout (PC4-21300), non-ECC, and ships as a single module, so it drops into one free DIMM slot without BIOS gymnastics or buying a whole matched kit. If your machine stalls when a browser full of tabs sits next to a game launcher and a chat client, a second stick of DDR4 is the most direct responsiveness fix available to you. Crucial is Micron's consumer brand, so these modules come out of Micron's own DRAM supply and go…
SpecPicks Verdict
SpecPicks scored Crucial RAM 8GB DDR4 2666 MHz CL19 Desktop Memory CT8G4DFRA266 using a rating × review-volume × price-fit model applied to published specs and reviews across the memory & ram category. Crucial's memory & ram lineup sits within the broader category mid-tier; price and specs are the deciding factors over brand loyalty here. Judge it on the specification table and the price rather than on sentiment: check the figures that decide your use case, then put it side-by-side with two or three close alternatives in the Compare tool before clicking through.
Common buyer scenarios for memory & ram of this kind: matching it to an existing build, replacing a failing part, or upgrading from a previous-generation equivalent. Check the spec table below against your current setup — particularly socket / form-factor / power-rating fields — and confirm compatibility on the retailer's listing before purchase. Prices and stock are set by the retailer and may have moved since this page was last updated.
Frequently Asked Questions
Will this RAM work in my desktop PC?
It fits desktops that take DDR4 2666 MT/s non-ECC UDIMMs in the standard 288-pin layout. Run the Crucial System Scanner or Crucial Advisor Tool on your machine to confirm your board's slot count, supported speed, and rank configuration (1Rx16, 1Rx8, or 2Rx8) before ordering.
Is this a single 8GB stick or a 2x8GB kit?
CT8G4DFRA266 is a single 8GB module. To run dual-channel you need two modules, so order two if both DIMM slots are open or you want 16GB total.
Can I mix this with the RAM already in my system?
Mixing works most reliably when the existing module matches on speed, latency, and rank. Mismatched sticks generally run at the slowest module's speed, and Crucial's compatibility assurance applies to the configuration its Scanner or Advisor Tool recommends.
Does this fit a laptop?
No. This is a 288-pin UDIMM in desktop form factor. Laptops and most mini-PCs use SODIMM modules, which are physically shorter and not interchangeable with this one.
Is it ECC memory, and what warranty does it carry?
It is Non-ECC, so it will not work in systems that require ECC memory for servers or ECC workstations. For current warranty coverage and terms, check the product listing or Crucial's published warranty details.
Key Features
- Improve your system's responsiveness, run apps faster and multitask with ease
- Install with ease; no computer skills required How-to guides available at Crucial
- Compatibility assurance when using the Crucial System Scanner or Crucial Advisor Tool
- Micron quality and reliability is backed by superior component and module level testing and 42 years of memory expertise
- ECC Type = Non-ECC, Form Factor = UDIMM, Pin Count = 288-pin, PC Speed = PC4-21300, Voltage = 12V, Rank and Configuration = 1Rx16, 1Rx8 or 2Rx8
Full Specifications
| Brand | Crucial |
|---|---|
| Voltage | 1.2 volts |
| RAM Size | 8 GB |
| Model Name | Crucial Memory |
| Unit Count | 1 Count |
| Form Factor | 288-Pin_UDIMM |
| Memory Speed | 2666 MHz |
| Model Number | CT8G4DFRA266 |
| Compatibility | PC |
| Item Type Name | DDR4 DRAM Memory |
| Number of Pins | 240 |
| Mfr Part Number | CT8G4DFRA266 |
| Number of Items | 1 |
| Memory Generation | DDR4 |
| Compatible Devices | Desktop |
| Data Transfer Rate | 1 megabits_per_second |
| Memory Form Factor | UDIMM |
| Additional Features | Lightweight |
| Computer Memory Size | 8 GB |
| Warranty Description | Limited Lifetime Warranty |
Ready to buy?
Crucial RAM 8GB DDR4 2666 MHz CL19 Desktop Memory CT8G4DFRA266 is listed on Amazon. Price, availability, shipping and returns are set by Amazon and its sellers — check the listing for current terms. SpecPicks earns a small commission on qualifying purchases — thank you for supporting independent review work.
*Price sourced from Amazon.com. Last updated 2026-10-06. Price and availability subject to change.
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