I agree with the assessments but try it without the battery for test run. I've seen old batteries tax the power supply that's on the motherboard and failures ensue like you wrote. However many are nonplussed over repair costs and once you hit so many dollars you have to think about replacing the machine.
"change bios to load defaults but it won't allow me" is interesting. But I can't tell what messages are on the screen or what stopped you.
Bob
I am fixing a notebook that has a bad hdd, ran chkdsk /r to fix, worked for a week, now getting disk read error, did diagnostic and identified hdd bad and also indicated battery too low to support system although battery indicator is 100%,installed new hdd, installed win xp pro, all went smoothly until final boot, getting disk read error again with new drive and upgraded 2gb ram. Checked many sites to find answer and they range from new power cable to new motherboard. Someone suggested I change bios to load defaults but it won't allow me to change this to test it. My knowledge is exhausted...

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