If it runs great in safe-mode, it is doubtful you have a hardware problem.
Check each of these items as steps to try and test, and not to try and do all at one time
* Adequate hard-drive Space
* Use MSCONFIG to disable all non-essentials programs loading (windows key press + R, type msconfig)
* Open Device Manager and make sure nothing has a problem indicated by an '!' by it.
* Have you done any recent driver updates? if so try to revert back. OR dump the driver and reload it (already have drivers downloaded before starting)
* Try one by one updating drivers if problem persists
Check back and let us know how it goes.. and yep troubleshooting requires (a) caffeine (b) patience (c) the occasional hair-pulling