A1,A2,A3 memory slots are not working

[jfs123]

hello i have 8/9 slots being used a1,a2,a3 are saying that they are disabled and i only get 40/64gb of ram i have put in i have swapped them around and it still says a1,a2,a3 are disabled this is a new build on first set up

 

[almartin]

Check your Bios and see if these slots are enabled. If not enable them.

 

[Leaps-from-Shadows]

To help you we need...
1. Detailed system specs
2. Detailed description of troubleshooting steps you have already taken