how to decrease that value i have only 8 gigs ram, half of it takes me graphics which should be enough for the games in which I play. however, they still require a little ram.
The "Shared GPU Memory" includes space in the page file on the HDD and space in RAM that's used when needed for unused graphics assets. For example, my shared GPU memory is 8GB, but it's only using, right now, 100mb of that. It's a Windows feature so games and programs operate correctly, not something you can adjust.
I would like to disable this function because in my case it causes too large decrease in performance, or at least reduce and limit this value. If the system decides about these values, then in the system registry there must be an entry that changes these values.
You could try asking on an OS forum, e.g. https://www.tenforums.com/