If you removed the HDD and can not get into bios:
.. You are not using the battery and are on the ac adaptor, are you sure it is good??
.. Next set, if sure it is not a memory problem, would be to remove the DVD drive. This is more a grasping at straw as There are not many things you can do with out disassembling it. Even dissasembling it, you are limited.
It does not sound like a bad CMOS battery, but for about $5 bucks it's worth a stab ( and reset/clear CMOS.
Unfortunately laptops, unless an expensive model, are not worth getting repaired.