You didn't mention whether or not you set the clock to current date and time. That can sometimes be an issue. As well, many BIOS have a failsafe mode and you might try that. It could be that Windows cannot configure some piece of hardware it thinks it hasn't seen. Worst case I've had to do to resurrect an old machine was to re-flash the BIOS to the same or newer version. It would be a last ditch attempt, however.
I have an HP Compaq dc7800p small form factor desktop pc. Anytime it turned on, it gave me the error about the time not being set and that the battery may need to be changed. I changed the battery to the same exact kind that was in before, same standard 3v battery. It won't load windows past the "windows loading" screen. At first, I thought this was just a bios setting, but for some reason, when the old battery is in the pc, it boots up windows. It just wont load windows with any other battery in it. Any ideas would be greatly appreciated!