Why can't I increase my vram above 512 mb?

[gopgop9000]

So I found out that the processor I have, the AMD A10-9600P has system shared memory for its integrated graphics,  which means I should be able to increase my vram as much as my RAM allows it to, however, when I go into the bios it only has 128MB, 256MB, and 512MB options. This does not make sense to me, as it should be allowed to have more, and I have read that other people have had this problem too, not necessarily with only this laptop. Is there any way to increase it or is it just capped at 512MB?

Computer:

Name: HP ProBook 455 G4

APU: AMD A10-9600P

RAM: 16GB DDR4 2400mhz

[iomare]

Hi,

The graphics RAM is shared with the system RAM and is a dynamic and automatic process. When more is needed, more is used. What you are setting is the dedicated (reserved) RAM and will be the minimum used, So, the integrated graphics will use more than 512MB when needed.

Regards,

David