OWC
OWC 128GB (4x32GB) DDR3 ECC Registered CL9 PC3-10600 1333MHz SDRAM Memory RAM Upgrade Module Compatible with All 2013 Mac Pro 6,1 Models (OWC1333D3Z3M128)
Bottom line: The OWC 128GB (4x32GB) DDR3 ECC Registered CL9 PC3-10600 1333MHz SDRAM ($452.72 on Amazon as of 2026-10-21 10:24 UTC, orderable but not in stock): Full 128GB kit (4x32GB) fills all four DIMM slots on the Mac Pro 6,1 in one purchase; main trade-off: locked to 1333MHz PC3-10600 with no headroom above the stock Mac Pro speed.
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*Price sourced from Amazon.com. Last updated 2026-10-21. Price and availability subject to change.
Pros & Cons
Pros
- ✓ Full 128GB kit (4x32GB) fills all four DIMM slots on the Mac Pro 6,1 in one purchase
- ✓ Mac-qualified thermal sensor EEPROM avoids the fan-ramp issue generic server RDIMMs cause
- ✓ ECC Registered PC3-10600 at CL9 1.5V matches Apple's stock 1333MHz spec exactly
- ✓ Limited lifetime warranty plus advanced replacement and free OWC tech support
- ✓ Cross-references seven OEM part numbers (Micron, Hynix, Samsung) for verified compatibility
Cons
- ✗ Locked to 1333MHz PC3-10600 with no headroom above the stock Mac Pro speed
- ✗ Fits only MacPro6,1 4/6/8/12-core Xeon models, so it carries over to nothing else
- ✗ Four 32GB DIMMs means no free slots left for a later incremental capacity bump
SpecPicks Verdict
SpecPicks scored OWC 128GB (4x32GB) DDR3 ECC Registered CL9 PC3-10600 1333MHz SDRAM… using a rating × review-volume × price-fit model applied to published specs and reviews across the memory & ram category. OWC'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.
Key Features
- OWC 128.0GB UPGRADE: Consists of a Four 32GB DDR3 1333MHz PC3-10600 CL9 ECC Registered DIMMs 1.5V 240-pin Memory Module with Mac qualified Thermal Sensor EEPROM
- 100% COMPLIANT: With JEDEC Standard Specifications, ROHS Compliant, Warranty Safe Upgrade. Designed and Tested to Meet or Exceed All MAC Specifications for Mac Pro 2013 6,1
- COMPATIBLE PART NUMBERS: MT72KSZS4G72PZ‐1G1, HMT84GR7BMR4A‐H9, M393B4G70BM0‐YH9, MT72KSZS4G72PZ‐1G4, HMT84GR7MMR4A‐H9, HMT84GR7AMR4A‐H9, M393B4G70DM0‐YH9
- COMPATIBLE WITH: Mac Pro Late 2013 Model ID: MacPro6,1 3.7GHz 4-Core Xeon & 3.5GHz 6-Core Xeon & 3.0GHz 8-Core Xeon & 2.7GHz 12-Core Xeon
- INCREASED PERFORMANCE: Memory Upgrades are the Most Effective and Easy Way to Boost the Performance in Your Mac Pro
- INDUSTRY LEADING: Consumer Friendly Advanced Replacement Program and Limited Lifetime Warranty, which Includes Free Tech Support by Other World Computing
Full Specifications
| Brand | OWC |
|---|---|
| Voltage | 1.5 Volts |
| RAM Size | 128 GB |
| Model Name | 1333D3Z3M128 |
| Unit Count | 4.0 Count |
| Form Factor | DIMM |
| Memory Speed | 666 MHz |
| Model Number | 1333D3Z3M128 |
| Compatibility | Mac |
| Number of Pins | 240 |
| COMPATIBLE WITH | Mac Pro Late 2013 Model ID: MacPro6,1 3.7GHz 4-Core Xeon & 3.5GHz 6-Core Xeon & 3.0GHz 8-Core Xeon & 2.7GHz 12-Core Xeon |
| Mfr Part Number | OWC1333D3Z3M128 |
| INDUSTRY LEADING | Consumer Friendly Advanced Replacement Program and Limited Lifetime Warranty, which Includes Free Tech Support by Other World Computing |
| Memory Generation | DDR3 |
| Compatible Devices | Desktop |
| Data Transfer Rate | 1333 MHz |
| Memory Form Factor | RDIMM |
| Additional Features | Ecc |
| OWC 128.0GB UPGRADE | Consists of a Four 32GB DDR3 1333MHz PC3-10600 CL9 ECC Registered DIMMs 1.5V 240-pin Memory Module with Mac qualified Thermal Sensor EEPROM |
| Computer Memory Size | 128 GB |
Ready to buy?
OWC 128GB (4x32GB) DDR3 ECC Registered CL9 PC3-10600 1333MHz SDRAM Memory RAM Upgrade Module Compatible with All 2013 Mac Pro 6,1 Models (OWC1333D3Z3M128) 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 2026-10-21. Price and availability subject to change.
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