How do I remove a strange rectangular sign superimposed on my monitor screen?

Several days ago, a 1-1/2" long x 1/2" wide rectangular sign mysteriously appeared on my monitor screen. It's centered equally from left to right and is 1" up from the screen's bottom. It's all dark gray , with a small football in the center, the right half of which is black and the left half the same dark gray as the rectangle. Beneath the football it says: 100% (in black). This thing is superimposed over whatever is on my screen and my mouse arrow slides underneath it.

I tried to remove it with my Avira AntiVir PE Classic, Ad Aware SE Personal, Spybot S%26D, SpywareBlaster, SpywareGuard, a-squared free, AVG AntiSpyware, Spyware Terminator, SUPER AntiSpyware and XoftSpy SE---all freeware---but they never detected it or removed it. Closing or restarting does nothing.

I feel that someone/something is telling me they've gained 100% control of my cmptr....otherwise why is it there and in such specific detail ?

Although my computer seems to run ok.

How do I get rid of this thing?

How do I remove a strange rectangular sign superimposed on my monitor screen?liveupdate

haha...

if it's what I'm thinking then you will laugh knowing what it is...

:))

ok.. juck check the buttons on your monitor......

try buttons that show up menu or the monitor editing program...

it's not any virus, no spyware...nothing... just your monitor contrast or brightness control saying that you monitor is setup for 100% brightness or contrast or something else.