Are WD Green Drives Really THAT Bad as the OS Disk?

Na they work, if you only shut down your system for windows updates you don't notice how slow they are. The main drag is that windows media center is pretty slow to launch, but eh. Once the OS boots its in ram and all your streaming services operate through your open browser so not much difference there. My HTPC runs of a single 2 TB WD green drive and I'm pretty happy with it.

Freezing and crashes could be caused by a faulty drive but if its working correctly it won't cause that. since it sounds like you have another drive sitting around swap it out, if the crashes go away then you know the problem.

My in-laws have a HTPC that has a Green drive as the OS and storage drive (too cheap to buy a SSD about a year ago when they were much more expensive) that I built for them. I also have 2 friends that have HTPCs that I have built for them that are now 2-3 years old that also have Green drives for the OS.

I haven't heard or seen any of the issues from them that you are describing. I also use the in-laws HTPC quite a bit when I am there to update it and haven't noticed any issues at all.

My first few HTPCs also used only Green drives and again, no issues (I am still using the drives from those systems as storage).

That's been my first-hand experience. YMMV.

I have 4 of the 2TB models in RAID 5 in my HTPC as my stroage drive. I had 1 failure in the last 2 yrs, they are fine for serving out my media but my OS is on a WD raptor.

How are you using XBMC? If your getting some freeze ups while using new PVR addons, then it's not the drive.

I'm on Frodo RC3, and Videos, Music, Pictures, menus, etc are all working fine but the Live TV portion has led to a lion's share of freeze-ups. It's not completely refined yet, but if you are getting freezes in your main content libraries like videos, music, etc then you've got a problem.

Check out XBMCbuntu or OpenELEC as well. Cheaper than an OS upgrade depending on your know-how and other intended uses for the HTPC

It could be memory related, but it seems very unlikely. It's hard to say without really looking at the complete overall usage. If your HDD activity light is going wild during these random events, then it probably is memory related. If you cap your available 3.33 the pagefile starts up and everything begins offloading to that green drive. It will make a slideshow of most computers until the page is emptied back into available RAM. Upping your RAM isn't a possibility, but it's more likely a memory bandwidth problem than a memory size problem. The only plausible "quick" fix for that would be a ready-boost enabled USB drive