As shown, Memtest is a tool for memory detection and why this option appears.
Baidu knows that some people have seen this problem, the solution is:
My motherboard is Ying Tai 890gtx, in the inside set the overclocking and then put the memory integration Test (M.I.T.) Changed from disabled to enable, the results repeatedly appear above the interface, and later read the manual is clear, this is used to detect the compatibility of memory after overclocking, you put it again by enable to change into disabled on the finish, I bold guess, You probably also moved a similar option in the BIOS settings, so you can change it back.
My solution:
Later found that the Ubuntu system boot kernel options when there is a memtest option, originally I modified the/boot/grub/grub.cfg inside the boot kernel sequence, set default=0 start the first option to start Memtest, Later only the reload system can be canceled into the memory detection interface, in fact, as long as the ability to repair the boot file, modify its startup options can be.
Ubuntu boot appears memtest86, restart can not cancel the reason