Start by giving system specs (monitor, graphics card, etc).
You say you only notice this in Windows? So which other OS are you using that you don't notice this in?
I've only noticed this in Windows:
I've got the correct drivers for my video card and even the monitor, but ever since this new monitor, windows has been blurring the whole screen real bad and then goes back to nice and crisp. Ive lessened the effect at times somehow, but i cant figure out exactly why causes this. how can i solve this issue? thanks

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