[SOLVED] Grey circle on monitor ?

Solution
Okay, so I have restarted my PC a lot of times, but for the fifth time, it disappeared, and I don't know how or why, but it's gone now. Thank you for the possible solutions though.
A tame graphics artifact being caused by a graphics card is possible, but extremely bizarre. Try booting a live linux (any distro will do) and see if it pops up. I suspect that it's software related. If it doesn't appear when you boot to linux, you'll know it's something higher level.
 
Okay, so I have restarted my PC a lot of times, but for the fifth time, it disappeared, and I don't know how or why, but it's gone now. Thank you for the possible solutions though.
 
Solution