not sure whether this is software, hardware, security, or none of the above, but i'll post it here.
it started happening during gentoo install. i had to reboot for some reasons and it tells me that there are no operating systems. i check my bios' booting sequence and my hard disk (i only have 1) can be expanded. i never noticed that. and after i expanded i see something weird stuff i don't even have... it's not removable something (cause that's the floppy) but it was something like that. weird. the other one i see is my real hd. so i move that up and it'll boot fine. btw, i seem to get this almost all the times. meaning that i randomly boot fine.

i get sick of doing that so i just load the default bios setting. i guess it's a trivial problem but just annoying. has anyone encountered something like this? any help will be appreciated. thanks.

Check the CMOS battery. You might try replacing it.

that sounds like the solution... but i wonder why the bios keeps changing not to the default? i mean i have to reset the bios to default when that problem occurs. if it's the battery issue that the bios settings are being reset.... .... weird.