Phantom OSX Drive shows up in BIOS Bootselect with no physical Drives attached

[Gemmenzwerg]

Hi,
I must have really screwed up. I ran the installer from my USB drive - then I rebooted with the USB drive and selected the installation. It showed the boot screen then ended up in the Drive-Utility. So I rebooted again and I chose the USB Drive again but it said not bootable. The USB does not show UEFI anymore but what is really bizarre is that as well as the USB drive I can select the SSD and I can select a drive called Mac OS X.
I tried selecting that - not bootable. I had called my SDD El Capitan - so what is this other drive?
I disconected the SSD and tried booting from the USB - not bootable - but the Mac OS X drive still showed up without any physical disc installed.
What have I done?
No USB Boot and a phantom drive?
Cheers
Gemmenzwerg

P. S. I attached my oldwindows SSD - that booted fine

 

[Gemmenzwerg]

After trying out a couple of things to narrow the problem I found out that other bootable USB Sticks (Win 10 and Linux) start booting and then stop. The El Capitan Stick does not even get that far - the BIOS says not bootable device.

The phantom device/drive called "Mac OS X" remains after leaving the computer turned off for 20 Min. While no drives are attached it shows up in the BIOS Boot Selection but not as a physical drive in the BIOS.

It was a result of the botched install and since then no USB has worked properly.

I really need help.
Thank you in advance.
Gemmenzwerg

 

[Gemmenzwerg]

The phantom drive seems to be the mac os x recovery tool - when you have a mac without an OS installed, the tool that lets you install from the internet, etc. But as this is a PC I am stumped on where it is written to and how to get rid of it. Especially as no bootable memory stick works anymore, I have a real problem.

I will see if flashing the Bios does anything.

That being said, I could use some help. Hasn't anyone encountered this behavier?

Cheers
Gemmenzwerg

 

[P1LGRIM]

Maybe this ?

[GUIDE] Remove extra Clover BIOS boot entries & prevent further problems

Clover is a great boot loader, and tonymacx86 has developed some great tools to get you up and running. However, some people are still having problems. I think a lot of this has to do with the design of the systems. Many have extra backup internal hard drives or partitions with legacy boot...

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