That's not a graphic card, that's a graphic chipset, usually found on laptops and sometimes on motherboards for desktops.
If your GPU has 8Gb VRAM, then you should plug your monitor on this instead of your motherboard.
If you're talking about RAM, it's not the same thing, RAM is not used only for graphic calculation, but to store datas for quick use, that's where textures and stuff are stored while you play, for instance, to prevent your PC from reloading it from the HDD every time.
RAM is some additionnal memory you have, it's small cards. VRAM is the memory your GPU can use.
Sorry it's a bit hard to explain it in english as it's not my main language.
Anyway, UHD Graphics aren't graphic cards, they are far less powerful