I have a sony vaio pcg-gr414sp laptop, I'm looking for the video driver for it, but can't find it anywhere

This model is pretty old - enough that Sony no longer supports it. If you don't have the original software repository off the C: drive or the recovery disks that came with the laptop, then you're stuck with buying drivers from 3rd party vendors (I found a few in a quick search). If you have the recovery disks AND a spare 2.5" hard drive (IDE, not SATA), then consider swapping the current drive with the spare one, and running the recovery disks on that 2nd drive. This will wipe out the contents of that drive, but it now holds the original software repository which has all the original drivers. You can make a CD of that driver directory, or pop the 2nd disk into an external USB disk case and use it to load the correct video driver for your original disk. This involves some money (spare hard drive and case) and opening your laptop to swap the internal drive.