Boot-up question

I am working on a Dell computer that seems to work fine, except
for when it is starting up. It recently had a hard drive installed
into it and while its running everything is fine. but in the time
between the first dell logo and the windows logon screen, it
takes insanely long. and whats even more suspicious is during a
boot in safe mode, it takes just as long to start up. this is before
the microsoft starts up so im thinking it is a driver problem
maybe. Can someone please tell me of some solutions or things
to look at?