OK. When Windows 7 crashes on startup at the logo, this usually means that there is an incorrect driver or a Windows Update that broke it. In rare occassions this can be caused by a virus.
If you did any updates to drivers or Windows recently, boot into safe mode and revert them. If this is not the case, you may have a hardware failure occurring when the hardware uses a particular function invoked or accessible by the driver. In which case you will have to try swapping hardware… But before you get to this, ensure you have exhausted your other options, including rebuilding Windows 7.