Need some help with a VAIO

OK here is my day so far. I have a Sony Vaio VGN FS640/W. CMOS went bad. Of course to get to the battery on a VAIO you have to rip the mother board out. So I replace the battery, put everything back together. When I boot it up it brings up the screen that ha VAIO on it then just hangs there? I pulled the HD and booted it and it does the same thing. It's like its not seeing the hard drive? I realize that there could be a multitude of things wrong here seeing as I had to disassemble almost the whole laptop to get to the battery. Ive done this on other laptops before and was real careful.
Any thoughts?

TIA

Brian

 

As you are probably aware, removing the CMOS battery resets the BIOS settings, you may have to enter the BIOS to make sure all settings are good to go, presumming you can actually get into the BIOS?