toshiba tecra 9100 shuts down after 1hrs use

I have a Toshiba Tecra 9100 running XP that shuts itself off after about a half hour of use. I tried to look in the toshiba power saver in control panel and it does not open, but if I click on power options it tells me to use toshiba power saver, but I can go see the battery is charging and how much life it has. It had 95% charge and it shut off by itself.
I have had this issue on and off for sometime. First time we thought it was the charger, I bought another one it was fine for a few months then started doing it again so i bought another one it was fine for a few months now it is doing it again. But now I get a message after the Toshiba screen "media test failure check cable existing intel pxe rom."

 

Thank you for responding and moving my post, I didn't know if I should start a new thread so i didn't.

I tried to restart my laptop but when I push the button it ( I can hear it) kind of winds up and just as soon as I think it's going into windows it winds down a abruptly shuts off. I will give it an hour or so I will sneak up on it and try it again.

 

Okay I started my laptop and the only thing that comes up during start up is the Toshiba screen and the error "media test failure check cable exiting intel pxe rom." then it goes into the windows screen. It does not tell me what key to push to enter BIOS.

 

Also your fans could be dirty with dust and no longer and move air property to cool your laptop.

 

Okay thank you I got into BIOS.
It says cdrom>lan>hdd>fdd
hdd priority builtin hdd second hdd network boot protocol = pxe

 

I cleaned the fans and air ducts, the battery is saying 75% charged and charging but it is still shutting itself down.
Can there be someting to the error "media test failure check cable exiting intel pxe rom" ?