Problem with monitor display...Weird!!

Bit of a wierd one this but hopefully you guys can help me as the seller or screen mfr haven't.

I have a DGM make of 24" monitor provided by Mesh as part of a system i bought last January (2008). The native resolution is 1920x1220 and this worked perfectly until about march when i was in the OSD changing the brightness. As i exited the on screen menu i accidently pressed the factory reset button and instantly the display shifted about 2 inches to the left (you can see the menu button at the far right as if the picture slipped off the left and the bit cut off appeared on the right) also the picture slanted by about 30 degrees and applied a yellow hue to all the colours on the screen!! The only way to resolve the issue is move to a different resolution. It runs correctly at 1024 x 768 but as soon as i try and go back up from that the problems return. I have twin 9800GT graphic cards running SLI and as i said before i pressed the factory reset on the screen all was perfect! DGM blamed the graphic cards and Mesh said it was a monityor issue!. Graphic drivers were removed and reloaded and then updated to see if it made any change but alas not.

Please help!!

Thanks