I installed a new Toshiba HDD on my laptop further to the old WD one "failing" (I'll explain the quotation marks later) and downloaded the various drivers from the Acer site. Once installed and other bits and pieces up and running, I suddenly strated getting BSODs (Windows has shut down to protect the o/s -type of message...). I thought I had tracked things down to an AHCI driver that was missing (I installed one off the HP site, but that wasn't the problem it turned out).

I couldn't figure out what was going on. I did notice that a BSOD had occurred when I turned the (running) maptop upside-down. I immediately thought some kind of metallic particle had gotten into the laptop and was causing a short. I tried doing a system repair from the W7 CD but there didn't seem to be any problems.

Then, I began having boot problems. The BIOS stopped responding about half-way through the boot and just hung. Soemtimes after 5 or 10 minutes, it let me boot to the CD. Sometimes not. Most times, I couldn't even get into the BIOS setting via F2...

Finally, before taking the Toshiba drive back to the store (or throwing it in the trash given my mindset by this time), I tried hooking it up to the second drive bay. Hey presto! Everything now works perfectly. Unfortunately, I can't put the drive bay cover back on with the HDD in place, so I'll have to come up with a custom solution.

My question is, if it's the HDD0 controller that is the problem, what would be the procedure to a) identify the problem and b) repair it ?

Many thanks