how many RAM memories are installed and what type?

The installed memory size is 64GB and the memory type is DDR4.

Questions & Answers: Refurbished: Dell Precision T7810 Workstation 2 x Intel Xeon E5-2630 V3 2.40GHz 16 Core 64GB DDR4 Memory Quadro K620 512GB SSD 1TB HDD Windows 10 Pro

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Dell Precision T7810 Workstation 2 x Intel Xeon E5-2630 V3 2.40GHz 16 Core 64GB DDR4 Memory Quadro K620 512GB SSD 1TB HDD Windows 10 Pro

Microsoft Authorized Refurbisher (MAR)
90 Day Warranty
New 512GB SSD, 1TB HDD
Great for Office Work, Rendering, and Data Calculations
Suitable for Online Learning, Homeschooling, and Back To School activities.
Capable of running Linux, Windows, Photoshop, Premiere Pro, AutoCAD, Blender and More!
64GB DDR4 Memory
Windows 10 Pro 64-Bit
2 x Intel Xeon E5-2630 V3 2.40GHz 8 Core
Includes Power Cable(s)