Color Banding issue

Hi, i recently exeprienced color banding on my games as well on the internet, it's like i'm in 16Bit colors when the resolution is set to 1080P 32Bit, here are some examples to illustrate this:

 if you look closely, you'll see color banding and tiny vertical lines on web pages like in the second pictures, i visited Nvidia forums, many of 'em are experiencing this trouble even with high end modern graphics cards and none have found the solution, i tried different version of driver, different graphics card, reinstalled the OS; reset the BiOS, used different monitors ... the problem is always here, i'm using an nvidia GTX560 Ti with an I5 3330 and 8Go of ram 1600Mhz, the motherboard is an MSI B75A-G43 Gaming.

PS:sorry for my english i'm french and i hope you will help me find a solution for this.

i've added download links for the pictures above to see more clearly because the image uploader scales it down to 720P:

https://mega.co.nz/#!8VdGTTCQ!KVjY2cuoH634pWVAoG_hDminD8pVratJuPrHTMJr7t0

https://mega.co.nz/#!xV0CWTpL!MWw3ZSFz0DpdHvUDCLOgLW9ZuTc_GMGXkLRKxE1A1o4

and i hate the spelling your instead of you're ...

anyway, i used another graphics card, tested with the integrated one, the problem is still present, also as i mentioned i'm using 1080P resolution with 32Bits colours depth, i didn't tested with the other pci express slot, because it's a 4X Gen 2.0 i think so i don't know if it's gonna work with the nvidia card.

this problem is driving me crazy, i don't think it's software related because i reinstalled the OS and nothing changed, i'm beginning to think that it might be the motherboard but how the hell did it happen?

as i mentioned, i tested other drivers (old and new ones) and still the exact same problem, as for the cable, my monitor has only VGA and HDMI, i tested them both, same thing, tested another monitor with a DVI i also got the same result.

can anyone help me?