Flaky Hard Disk - Can't read at all.

So I've got two hard disks in my system, one is a 150 gig IDE drive for OS and essential apps, the other is a 500 gig SATA drive for documents, games, and all other apps. The 500 gigger is where the issue is. It's a Hitachi model. I can load Windows and my background tasks, load Steam, Firefox, anything that's on the drive, but after maybe a half an hour the drive cuts out; The system stops recognizing it, disappears from My Computer, and does not appear in the device manager. It's as if I had ripped the SATA cable out of the drive. The most annoying part is that it happens in the middle of a TF2 game, and as soon as it tries to load a new sound or texture, the game freezes, along with Steam. I've poached my brain trying to solve this, and I believe I just might have to get a new drive. It's not old, and no SMART warnings, only unboxed the drive three months ago with my new build. I've gone weeks without the issue, and it's just happened minutes ago. Restarting fixes it temporarily, but it's a span of minutes to a few days before it happens again. Has anyone else had this issue, or any like it? Is it indicative of a failing drive? I should mention that I'm using Windows 7 RC.

Any help is much appreciated!

Punch the hard drive's model number into google to see if other people have had this problem.

power issues or maybe a bad cable?

I've heard rumors of Windows 7 having issues with the D drive...
I personally have not had any issues, however.