Remove custom message from bios

I bought a computer from someone it is a dell optiplex gx620 and when you turn it on as the dell screen shows there is a custom message at the top that I can not figure out how to remove.I have done a clean install of windows.I guess it is something in the bios.I have tried to flash the bios but still the message is there.Does anyone have any ideas on getting rid of this message?

 

Hi, is this message there all the time the computer is on, or does it only show when first turned on?
If it is there all the time, is it possible to show us a screen shot of that message please?
As far as the BIOS is concerned, one of our other moderators is possibly more familiar with that, and once she knows what the message is and the other details I ask for, she may be able to help better than me.

Nev.

 

It is only when it comes on.It is when the computer is booting up....the computer was bought at an auction and the school name is what is showing up.. Humble Independent School District is what I'm trying to remove

 

Obviously manufacturer installed possibly at the request of that school when they bought it and near impossible to remove. They are made that way as a means of identification if stolen as it is imprinted into the BIOS chip.
If selling it on, and was from a genuine auction redundancy sale, you will need the paperwork to prove it was bought in genuine circumstances.

Nev.

 

Hi.
You could check the Bios Setup menu and disable "Quiet boot" and it will show the post data and disable the Vendor image.

 

DSTM got it!