Boot from card reader HP 8300

[gabizro]

According to user manual for HP 8300 SFF under Solve media card reader problems (page 264)

After inserting a media card in the reader, the computer attempts to boot from the media card.

Cause

The inserted media card has boot capability.

Solution

If you do not want to boot from the media card, remove it
during boot or do not select the option to boot from the
inserted media card during the boot process.

OK now.

I want to boot from Media Card reader.

Tested two card reader

MCR22iN1-5181

HP P/N 468494-003

None of them are able to boot from card.

USB boot is enabled,same card inserted in another reader that is inserted into Card reader USB connector boot fine,either legacy or UEFI.

Also both card readers tested on another PC (Asus motherboard) are able to boot from card reader and same card.

How to solve this?

To make more clear.

HP

Motherboard -  MEDIA connector          

< -USB socket - no name card reader < -  card x  is present in boot menu   - bootable

<-HP card reader <- card x     ------ ------------                                                   NOT present in boot menu

.

Other PC

Motherboard -two usb ports connector

<-USB socket - no name card reader -  card x  is present in boot menu   - bootable

<-HP card reader <- card x     ------ ------------   is present in boot menu - bootable

.

Tested in both MEDIA connector of HP board.

card x was same in all tests.

Once OS started both cards reader works fine in HP.

So the problem must be from HP 8300 (BIOS i think,somehow block their own card reader to be able to enumerate as a boot device)