Crucial
Crucial Pro 128GB Kit (2x64GB) DDR5 RAM
Bottom line: The Crucial Pro 128GB Kit DDR5 RAM: 128GB in only two DIMMs, leaving slots free on 4-slot boards; main trade-off: CAS latency 46 is loose versus enthusiast-tuned DDR5 kits.
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Pros & Cons
Pros
- ✓ 128GB in only two DIMMs, leaving slots free on 4-slot boards
- ✓ Intel XMP 3.0 and AMD EXPO profiles on the same module
- ✓ Low-profile matte black spreader clears tall air coolers and SFF cases
- ✓ Built-in 5200MHz and 4800MHz downclock fallbacks for picky boards
Cons
- ✗ CAS latency 46 is loose versus enthusiast-tuned DDR5 kits
- ✗ 5600MHz is baseline speed, not a high-frequency overclocking kit
- ✗ Dual-rank 64GB DIMMs often force lower speeds than 16GB/32GB sticks
- ✗ Needs Core Ultra Series 2, 14th Gen Core, or Ryzen 9000-class support
Manufacturer description
The Crucial Pro 128GB DDR5 kit (CP2K64G56C46U5) pairs two 64GB UDIMMs at 5600MHz with CAS latency 46, giving you top-tier capacity without stepping up to registered server memory. If you are running local LLMs, 4K video timelines, or a dozen Chrome tabs behind a game, 128GB is the tier where you stop managing RAM and start using it. Crucial rates the kit for the latest Intel Core Ultra Series 2 and 14th Gen Core CPUs plus AMD Ryzen 9000 Series and above, and it carries both Intel XMP 3.0 and AMD EXPO profiles on the same module, so one kit recovers its rated speed on either platform from the…
SpecPicks Verdict
SpecPicks scored Crucial Pro 128GB Kit DDR5 RAM using a rating × review-volume × price-fit model applied to published specs and reviews across the processors category. Crucial's processors 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 processors 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 128GB kit work with my CPU?
Crucial lists compatibility with Intel Core Ultra Series 2 and 14th Gen Core CPUs, plus AMD Ryzen 9000 Series desktop CPUs and above. It is a standard 288-pin DDR5 UDIMM, so any board accepting DDR5-5600 UDIMM memory is the target. Check your motherboard's QVL for 64GB dual-rank module support before ordering.
What speed and latency does this kit actually run at?
It runs at 5600MHz with a CAS latency of 46, and supports downclocking to 5200MHz or 4800MHz. If your CPU suppresses the rated speed, enabling Intel XMP 3.0 or AMD EXPO in the UEFI/BIOS restores it.
Is this a 2-stick kit or 4 sticks?
Two sticks: the CP2K64G56C46U5 kit is 2x64GB. That leaves two slots open on a four-slot board and is easier on the memory controller than populating all four.
Will it fit under a large air cooler or in a small case?
Crucial uses an integrated low-profile matte black heat spreader on the Pro DDR5 line specifically so it clears tall coolers and fits smaller PCs. Measure your cooler's DIMM clearance to confirm.
Key Features
- Elevated performance for gamers & creators: 128GB kit DDR5 for enhanced productivity—accelerate demanding tasks and enjoy higher frame rates with this high-speed RAM
- Enhanced PC performance: Crucial Pro RAM 128GB kit with 2x64GB DDR5 operating at the speed of 5600MHz with 5200MHz or 4800MHz downclock support
- Top-tier RAM capacity: 128GB DDR5 RAM kit (2x64GB) compatible with latest Intel Core Ultra Series 2 & 14th Gen Core CPUs and AMD Ryzen 9000 Series desktop CPUs and above
- Low-profile, matte black heat spreader: Enhance your gaming rig with a sleek, modern look. With our integrated low-profile heat spreader, Crucial DDR5 Pro can even fit in smaller PCs
- Supports Intel XMP 3.0 and AMD EXPO on the same module: Achieve easy performance recovery on CPUs that suppress rated memory speeds with Intel XMP 3.0 or AMD EXPO turned on in the UEFI/BIOS settings. Get the full value of your investment without overpaying for performance
Full Specifications
| Brand | Crucial |
|---|---|
| Voltage | 1.1 Volts |
| RAM Size | 128 GB |
| Model Name | Pro 128GB Kit DDR5 RAM 5600MHz Desktop Gaming Memory |
| Form Factor | DIMM |
| Memory Speed | 5600 MHz |
| Model Number | CP2K64G56C46U5 |
| Compatibility | PC |
| Built-In Media | Item |
| Number of Pins | 288 |
| Mfr Part Number | CP2K64G56C46U5 |
| Memory Generation | DDR5 |
| Compatible Devices | Desktop |
| Data Transfer Rate | 5600 MHz |
| Memory Form Factor | UDIMM |
| Additional Features | Registered Memory |
| Computer Memory Size | 128 GB |
| Warranty Description | Limited Lifetime Warranty |
| RAM Memory Technology | DDR5 |
| Top-tier RAM capacity | 128GB DDR5 RAM kit (2x64GB) compatible with latest Intel Core Ultra Series 2 & 14th Gen Core CPUs and AMD Ryzen 9000 Series desktop CPUs and above |
| Full listing title | Crucial Pro 128GB Kit (2x64GB) DDR5 RAM, 5600MHz (or 5200MHz or 4800MHz) Desktop Gaming Memory UDIMM, Compatible with Latest Intel & AMD CPU CP2K64G56C46U5 |
Ready to buy?
Crucial Pro 128GB Kit (2x64GB) DDR5 RAM, 5600MHz (or 5200MHz or 4800MHz) Desktop Gaming Memory UDIMM, Compatible with Latest Intel & AMD CPU CP2K64G56C46U5 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.
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