Windows 7 Pro freezes on Lenovo Y430 ideapad

I installed Windows 7 Professional 64-bit on my Lenovo ideapad Y430 (which came with Vista Home Premium 32-bit). It worked fine for a few hours. However, it now freezes up within 1 minute after I sign on after rebooting. The cursor stops moving, Task Manager won't come up, no disk activity, etc. Booting in Safe Mode works fine, so I'm thinking it's an issue related to a driver or service that doesn't load in Safe Mode. Event Viewer doesn't reveal much of use; only the fact that I needed to power off without shutdown. Vista still runs fine on another partition.

Has anyone seen anything like this, or have any ideas on how I can get Windows 7 running again (e.g., by identifying and removing/updating the offending driver/server, if that's what's causing the problem)? Any help would be greatly appreciated, thanks!

(Self-plagiarisation: )

The fact that it seems fine (as it's never happened - not even once?) in safe mode is A Good Thing, because it suggests that the causes are software-based. Something that loads in normal mode but not safe mode is presumably the culprit.

One way to start troubleshooting is with the MSCONFIG utility. Start off by choosing the "diagnostic" startup mode and rebooting. If that works, as in there are no hangs, go to "selective" startup and disable/enable the various optional components until you zero-in on the culprit.

If "diagnostic" mode doesn't stop the hangs from occurring in normal mode, uninstall your anti-virus and any 3rd-party firewalls (disabling them is not enough). Test what happens when running without them.