I'd have to agree, 1.8v for vanilla 1600mhz ram is too high. I know some of the specialist ram can need a few more v but 1.8v sounds too much. My own 1600mhz Corsair Vengeance ram uses 1.5v.
Btw: on my ASUS P8Z68-V Pro motherboard, XMP isn't always as reliable as it should be. For example, I had 2x4gb and 2x 8gb DIMMs, the former being 9-9-9 the latter 10-10-10 yet XMP forces the lot to 9-9-9 causing instabilities. Once I manually set the timings to 10-10-10 (plus the other bits of course) everything was fine...
Hope you ram isn't fried, but I'd not be surprised if it was.
Best of luck - worse case Ram is fairly cheap currently, so replacing it shouldn't sting too much.
Scoob.