Also from log previously attached, following string is written to address out of this word, isn't? Look like some return address than HEAP, right?
0009:Call KERNEL32.MultiByteToWideChar(0000fdf2,00000000,0021cac8 "HDA NVidia",ffffffff,7dfc9ee4,00000020) ret=7dfb2ae4 0009:Ret KERNEL32.MultiByteToWideChar() retval=0000000b ret=7dfb2ae4