PC wont boot when I remove secondary hard drive

Hi guys,
I'm trying to remove an old secondary drive which is making an annoying noise but when I do my pc wont boot. It just has a black screen and nothing happens. I think the problem might have come from when I installed ages ago and kept both drives in. How can I change it so it boots from my main drive? Any help is much appreciated.

So you have 2 hdds...does each have a OS on them? If so, sounds like the MBR for both hdds are on the same hdd. The one you're removing. You can use some 3rd party software and move the offending MBR to the correct drive......
Best Free Partition Manager for Windows | MiniTool Partition Free

Agreed. Conventional wisdom suggests unplugging all drives except the ODD/Optical Disk Drive and the C: or intended boot/system drive before installing an OS/Operating System just to prevent such a situation happening. Frequently doing Win10 Upgrades, such as from Version 1511 to Version 1607, can be an issue with External USB drives plugged in at the time.

SoFine409 said:

Hi Freddy1013 and welcome to the forums. You might have installed Win10 and the boot files ended up on the second HDD. Take a look at post #3 from this thread Can't re-establish Master Boot Record on my Windows 10 Boot drive - Solved - Windows 10 Forums. It should fix your problem. I did the same thing a while back.
Bob

Thank you! Once I figured how to get into bios that worked perfectly. If I'd know it was so simple I would have done it ages ago. The hard drive noise was making me go nuts. Thanks again!