T5820 memory compatibility

Hello,

First post in here,  I need to upgrade some T5820 to 256GB of RAM,  I've ordered 64GB sticks from Kingston model KTD-PE432/64G .  

When I replace the 32GB DIMMs from the workstation for the new 64GB DIMMs, on powering up, I only have a black screen.  Do I need to update BIOS ?

Thanks