system memory? you mean just RAM?Yes...it just means the program will resort to using system memory/storage to make up the difference...so it will be slower than if you had 4gb on the gpu.
Then it's good, i have 16gb of RAM.
I know ;( but i have laptop and i can't get better graphics card :/It will help but it will still be slower than gpu memory.
What type of program?Can i open programs what needs 4gb vram?
maybe future dying light 2?What type of program?
Usually with insufficient amount of vram you can expect some weird effects, which basically make the program unusable.
For example in games you may get objects appearing/disappearing, various visual artifacts, corrupted textures and more.