Recently I was attempting to boot from a USB into a thumbdrive MS-DOS, but as I was in the BIOS settings tab (phoenix bios, in case it matters) the computer froze. I tried hitting buttons etc, but eventually I simply turned the computer off by holding the power button. After that, I tried turning the computer back on without the usb plugged in, and it did not make it to the bios.
I hit the power button (the cord was plugged in, the battery was fully charged as well) it turned, but did not boot, the fan simply ran as if the computer was hot (which it wasnt) and the screen was black. Pressing the eject button on the CD drive opened the drive, and when I tried running a cd (a blank one) I could hear the disk spinning and the machine reading it (for all I know).
Another peculiar aspect is if I plug in the powercord (battery or not) the computer instantly turns on, without me pressing the power button at all. I replaced the CMOS battery, but still no cigar.
Please let me know if you understand what's going on!