W10 running the latest update. Up until recently when I booted my computer it went to a black screen that told me to choose what OS to load. This was because at one time had a dual boot. I had removed the 2nd OS previously but it still asked me to choose. So I had to click on W10. I got tired of having to do that all the time so I used Easy BCD to remove the second OS choice. After this my boot time increased from about 35 seconds to over 2 minutes. I couldn't figure it out. Then, my 1TB backup drive bit the dust. Today I received a new 1TB drive from Amazon and removed and replaced the dead drive. Without making any other changes my boot time is now back to 35 seconds. Go figure!!! I have no clue how this could have changed things but I'm glad it did.