Windows7 x64, Illustrator CS6 x64, AMD Radeon HD 6770 1Gb.
On creating or moving any objects I have artifacts like this:
They drawing to the right of the cursor till I hold mouse button. After release button they mostly disappeared.
Sorry my english.
Could be your graphic card see if it has updated drivers?
It was my first thought. I'm reinstalling video drivers already 2 times.