Long time til boot

I am having a problem w/ my Lenovo laptop.

It takes forever to boot up, & that's after trying to restore from an earlier point, boot in safe mode, etc. Every option there is, I do. However, it all changes when it FINALLY loads up. Not one thing works; I just get lucky.

I have tried to find a certain pattern, but like I said, it finally boots up after constantly turning it off, turning it on, safe mode, restore, etc.

When it finally does boot, it takes awhile on a black screen, & then it's there.

I know it's weird, & I did a search on the forums, but haven't found one that is like mine.

I've also done a scan for viruses using Avast! & MalwareBytes. Nothing comes up.

Thanks for any help!