That is just a normal run of the mill 2.5 inch laptop drive.  It spins at 5400 rpm, so it's kind of a slow drive too.  You can replace it with pretty much any other laptop drive.  Although, for a speed increase you might want to replace it with an SSD.

My HD is failing and I need to replace it. I have a wd5000bevt - 75ZAT0. Do I have to replace it with another wd? Or how do I know what is compatible?

jdsabere

No, any 2.5", 9.5mm High, 5400/7200rpm, internal notebook hard drive will work.

Bev.

 it will not have any impact even if you go for other HDD vendors. Just check the HDD form factor of your present WD hard drive (wd5000bevt - 75ZAT0) (its a 2.5") & go for the one which is similar to it. Capacity & RPM does not matter in this case.