The amount of system ram should be fine, make sure to use skse to have skyrim take full advantage of the available ram as well as enboost. Also by radeon hd graphics is that mobile graphics or is a graphic card or is it integrated graphics? You can use a tool named speccy to find out exactly what hardware you're running if you are unaware. In terms of memory it should be fine if you have at least 1gb vram as well, the 8gb system ram should be helpful as long as you use skse and enboost and set it up correctly. 2k textures might be your biggest issue since it takes lots of vram, might want to get 1k textures instead unless you have 2gb vram or more. My 6870 1gb gets kind of stutters with 2k textures and ctd more unlike with 1k textures where it runs fine.