they put that warning there now because lat year when gigabyte came out with there top mb an overclocker put a video up of one frying when it was brand new going into burn in. the issue at the time was that durning burn in or over clocking with the new digital vrm you could pull more power then the vrm could supply and cause them to burn out and catch fire. some vendors had to run new bios code that would not let the end user pull more power then the mb could give. the parts on a mb are rated for some overclocking but in a burn in test your maxing out the ram..cpu..video and power supply at 100 percent max. sometime doing that can be harder on the mb then what it rated for.
My las mobo was MSI.. it had 2 years warranty.. 2 years and 16 days, it was dead.. and now this?!!
I can say honestly I will not buy MSI mobos again... if they don't trust their products, I don't trust them.
all of us here on the forum will tell you we all gotten bumb parts before. i gotten monitors that been doa right out of the box. you have to do your homework today to see what vendors have the best return warranty today and the lowest defects. i would email msi and see if they give you a warranty exception that it was close to the two years. sounds like a cap might have gone bad on the mb.