alter ram used by igpu with bar edit

As my BIOS according to the ifr file cannot modify the operation of the igpu I found a program called bar edit, I found the location of the device in it but I don’t know where to start I attached an image to see if someone helps me

Edit by Fernando: Thread title specified and customized

looks interesting will this work for laptop ryzen APU? i could not set the Vram even when i poke with the UMA settings its locked to 1GB
this is no longer a problem for the newer intel chips since it uses shared ram for the iGPU so this tool will no longer be needed