My wide-screen U3423we has gone blank after only a couple of months. The self-test doesn't work as there is no dialogue box, although I can see that there is a slight brightening of the black screen when I tunr on and off - so there is power. The PC (W10, 64bit) does recognise there a screen connected (although I disconnect, as the manual instructs, for the self-test). Has anyone had a similar problem and know of a fix? Or is it just a faulty product?