Acemagic RX16 (AMD Ryzen 9 6900HX) : configure VRAM for iGPU Radeon 680M

[GRTN]

First of all we have to access UEFI operating system .
From my configuration in dual boot with Ubuntu 24.04 and Windows 11 , I called Restart and during startup program GRUB offered me ‘UEFI System Settings’ which I selected by up / down arrow keys on keyboard and Return key .
In case of Acemagic RX16 with only Windows 11 UEFI operating system can be accessed with usual prodedure ‘Start --> Settings --> System --> Recovery --> Advanced Startup’ and then pressing button ‘Restart Now’ : an interface allows to choose option ‘UEFI : …’ by arrow keys on keyboard and then pressing Return key on keyboard once selected relevant option of interest .
Once inside UEFI operating system , a window with title ‘Aptio Setup – AMI’ appeared , I selected tab ‘Advanced’ by left / right arrow keys on keyboard , then I selected option ‘GFX Configuration’ by up / down arrow keys on keyboard and pressed Return key on keyboard .
A popup window appeared where options for VRAM are listed , I selected ‘8 GB’ and pressed Return key on keyboard (to my surprise there is also option ‘16 GB’ but I didn’t choose it because manufacturer’s data sheet declare Ryzen 9 6900HX configurable to max 8 GB of VRAM : if anyone among readers of this post has more updated information on this feature , please insert a reply to this post with relevant additional information) .
Then I pressed Esc on keyboard and moved to tab ‘Save & Exit’ by left / right arrow keys on keyboard and I chose to save my updates on configuration of CPU/iGPU .
Then Acemagic RX16 restarted and after a while desktop of Ubuntu 24.04 appeared . I made a check by opening a terminal and executing shell command ‘lshw’ . Among relevant information on all components of the system appeared :
...
memory description : System Memory
→ physical id : 0
→ size : 56GiB
…
Everything looked fine , given that already I had expanded my Acemagic RX16 to 64 GB with two 32 GB SO-DIMM DDR5 , and 56 GB of system memory + 8 GB VRAM allocated to iGPU use 64 GB of RAM overall .

[GRTN]

Additional information :
I forgot to mention that , from option ‘GFX Configuration’ , it should be chosen option ‘UMA Frame Buffer Size' and it is this last one that opens popup window where to choose option for ‘8 GB’ for memory allocated as iGPU VRAM . (Sorry ! Sob! )
By the way , on Acemagic RX16 just delivered from manufacturer’s factory with only 16 GB of a single SO-DIMM DDR5 by default AMD Ryzen 9 6900HX is configured with 14 GB of system memory and 2 GB VRAM allocated to iGPU .

[GRTN]

Just for the record : I have also an Acemagic AX16 with Intel N95 processor and 16 GB RAM DDR4 .
I made same test with shell command 'lshw' and I got :
...
memory description : System Memory
→ physical id : 0
→ size : 15GiB
…
So it looks like VRAM allocated to iGPU of processor Intel N95 , on a system with 16 GB RAM , is configured by default to 1 GB .
Accessing UEFI of manufacturer Intel for N95 processor there are a hell of a lot of parameters that can be configured , but no parameter to set VRAM size . It looks like VRAM size can be configured by users only on systems with AMD processors .
I wonder whether UEFI for AMD Vega 8 iGPU , that’s to say AMD 5700U o AMD 5825U processors , allows users to configure VRAM size similarly to what provided by UEFI for AMD Ryzen 9 6900HX , but I don’t have on avail any computer with these processors . Is there anybody else able to check UEFI for VRAM size configuration on a Acemagic AX16 Pro ?