Hi all! I recently purchased one of Western Digital's new 12.5mm drives, the 750GB version with model no. WD7500KEVT. I've previously replaced my DVD burner with an Intel X25-M G2 80GB with no problems whatsoever. I put the 750GB drive where the stock 160GB used to reside (because there's better vibration damping there than in the DVD caddy). First thing I did after turning on my MBP was to copy about 160GB of movies from an external drive to the new WD drive. 2/3 through the transfer just paused with no explanation whatsoever. Nothing happened for about 30 minutes or so so I cancelled the transfer. After this the drive was no longer working properly. Sometimes I could transfer a few GBs of files but mostly the drive wouldn't respond at all with the transfer window stuck at "preparing to copy files" or "zero kb of X GBs transferred". I've tried just about anything but the drive refuses to work. This is some of the stuff I've tried without success: Erase and partition in Disk Utility (which btw hangs most of the time when the drive is connected) many, many times Removing the battery connector for a few minutes (guess this is the same as removing the CMOS battery on a PC motherboard?) Clean install of Snow Leopard Testing the drive without any of the Snow Leopard updates applied, including the "pausing HDD" patch Edit: Including Performance Update 1.0 Inserting the drive into a Windows 7 PC, the drive works flawlessly, at least for the 15 minutes or so that I tried it. I even bought the 500GB version (WD5000BEVT) but I got exactly the same problems with that drive. I'm writing all this because I want to see if anyone else have heard about any problems with these drives in Snow Leopard and if anyone knows of a fix. Thanks in advance!