I don't get it: T7810 does not accept non-EEC type...right?

The product is described as ECC Registered DIMM memory, which means it is ECC (Error-Correcting Code) type memory and compatible with Precision Workstation T7810.

Questions & Answers: CMS 64GB (4X16GB) DDR4 17000 2133MHz ECC REGISTERED DIMM Memory Ram Upgrade Compatible with Dell® PowerEdge FC430, Precision Workstation T5810, Precision Workstation T7810 For Servers Only - B102

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CMS 64GB (4X16GB) DDR4 17000 2133MHz ECC REGISTERED DIMM Memory Ram Upgrade Compatible with Dell® PowerEdge FC430, Precision Workstation T5810, Precision Workstation T7810 For Servers Only - B102

Computer Memory Solutions guarantees compatibility with models provided in description.
Memory Type: ECC Registered DIMM, 288-Pin
Speed: DDR4-17000, 2133 MHz
4 Piece Kit
Product appearance may vary. Picture for reference only. limited lifetime warranty when bought directly from computer memory solutions

$239^.50 –