replaced cmos battery now my laptop wont go pass dell start up screen

My cmos battery (the one on the motherboard) was dying since my clock was always wrong and i would lose the connection from my wireless internet.

i replaced it following the steps on the dell manual.

now my laptop wont go pass the dell start up screen. as soon at it hits the windows screen it reboots. and it just repeats the process.

system:

            dell studio 1535

            bios ao5 (revised 2008)

            vista home

i went through a similar post here:

http://en.community.dell.com/support-forums/software-os/f/3524/p/17863969/17986955.aspx

and i think my computer just wont read the hard drive....

my bios options are:

system

onboard devices

video

security

performance

power management

maintance

post behavior

wireless

i cant find drives