Need a lesson in ddr4 reg memory

[rsutoratosu]

This is the memory I bought, unfortunately it wont post in the machine.. spec wise they look the same.. Unless they're not.. am I missing something..
So I bought 4 of the bottom one and they work but curious why the samsung one doesnt. 4 new sticks, I tried each on individually. I know it boots with 1 stick for testing purposes


https://www.memory4less.com/samsung-8gb-ddr4-pc17000-m393a1g40bb0-cqb

DDR4 ECC REGISTERED MEMORY - Samsung M393a1g40bb0-cqb


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This is what comes with the system

https://www.ebay.com/itm/SK-Hynix-8...NwAAOSwoMZcmcHW:sc:USPSFirstClass!11354!US!-1

Hynix 8GB DDR4 2133 MHz 288-pin ECC REG 288 pin 1Rx4 Server RAM. Model number HMA41GR7AFR4N-TF

 

[hojnikb]

Maybe there's a bios whitelist for DRAM. In that case, you'd need to source RAM directly from HP or whoever the manufacturer is.