So, I was happily copying files around on my Windows Home Server, when I noticed that the speed of the transfers were now at 1.5MB/s… Uncool, when copying similar files from the same directories was at 50-80MB/s minutes earlier.

I tried to think what I might have changed since it worked fine. I tried reseting the CMOS, disconnecting all hard drives (IDE, USB, SATA) that were connected, except my primary drive, to no avail. OS was still very slow to load, and when I did let it load, I still measured 1.5MB/s transfer speeds using HDTune

I finally found a solution. Disconnecting the SATA data cable from the first SATA port on the motherboard (where it was always connected), and connecting that same cable into the last SATA port. Bingo! Instantly, I’m back transferring files at decent speeds. I don’t know the exact cause of the problem, and I didn’t yet try that 1st SATA port with other hard drives, to see if the problem is with the port, or the hard drive & port combination. What’s important is that it now works fine!

I have to thank this guy for the idea on how to fix this.
I guess I would have tried that at some point, but at least now I know I’m not the only one who had this problem. And I’m reposting the solution here, just to insure anyone else who faces this particular problem in the future can find this solution faster than I did!