I got a customers M17x R3 that has had bad video card issues for the last two years. Originally had a 580m that died. I swapped in a 680m, doing the unlocked bios and vbios mods. That card died after a year, swapped in a 7970m. That died after a few months. Found a new sealed 580m and swapped that in. Now I'm getting 7 beeps with the card in. No card, boots right up. Card back in, 7 beeps. Tried CMOS reset. Tried flashing back to factory A12 (since using a 580m again), still getting 7 beeps, which is showing as CPU error. Any thoughts? Motherboard issue (maybe killing the other cards)?