My computer won't start after a changed boot order.

[majed.azar7]

I usually don't write on forums but i've got an emergency :
- My friend gave me his pc because he wanted a new windows
- His pc an old has windows xp, 0.5gb of ram with dual-core (pretty old in 2019)
- When I booted Windows on my usb flash drive, i couldn't make the pc boot from it so i thought that maybe, if i change the boot order in the bios, it'll work. So i did.
- No the pc doesn't even turn on. You can't even access the bios. He's making a buzzing noise even 5 seconds with some yellow coming from the cd player as if he wanted me to put a cd inside.

So. My main question is : how can i access on more time the bios to change ? (I told him that I was gonna give him the pc tomorrow.... please guys... somebody help me :,( )

 

[rgd1101]

old pc can't boot from usb
unplug the power, unplug the cd/dvd player. then try boot it up and go to bios.

 

[majed.azar7]

I already did. I tryied to unplug the battery, press the power button for 20 seconds but when i put it back in nothing change.
I also tryied to take out the ram for a while but it's looks like nothing has changed.
Isn't there another way ?

 

[majed.azar7]

Also when the laptop was working it had the option of booting from usb when i pressed esc. It was in the boot option but when i selected my usb, he just ignoried it.
That's why i tryied to change the boot order right from the bios...