12 GB is installed, but the PC sees 8 GB, how to enable VKU?

Question

Iron

Hello. It was 8 GB, added + a die for 4 GB. In the BIOS, I flipped through the broken RAM and he sees 3 dice. But the bios says 8GB of RAM. Here's how to enable all 12 GB)

Answer 1

The limit can be set in the system. To remove it, open the command prompt and enter the msconfig command - the "System Configuration" window will open (you can also use the Windows search by the name of the window).
In the window that opens, go to the Loading tab and click on Advanced options.
Check that the Maximum memory box is not checked or there is no value that is less than the amount. Otherwise, just uncheck the
Source

Answer 2

What does it say on the manufacturer's website?
If the mother is old, then maybe she just can't do more than 8