Okay, I have read a bunch about this topic and it's relation to AHCI, but now I would appreciate some help. I have a Sager NP9280 (Clevo D900F) which has an X58 board with the Intel ICH10R controller, and 3 drives in RAID0. I just got an eSATA but no matter what the drive is not recognized. At one point it showed up briefly in the Intel Matrix software but then the program keeps refreshing and looping searching for new devices. At one point I gave up and just unplugged the drive didn't think much of it because it wasn't being recognized even in the RAID controller settings, but it somehow it broke my windows boot record but windows recovery was able to fix it. I just want the eSATA drive to work. QUESTION 1) Do I have to enable ACHI? My BIOS only has RAID and AHCI options and when switching to AHCI, Windows does not boot. QUESTION 2) Can I still use RAID in AHCI mode? I also read I have to reinstall Windows after switching to AHCI, but QUESTION 3) can I install Windows with an Image backup? I think the answer is yes but I just want to be sure. EDIT: First off, thank you for the help so far. when I was a 10 year old child I came here and got help with how to upgrade my graphics card. I guess things have changed. or I have just become more impatient. </rant> So exactly what happens and how it happens is that I plug in and power on my external eSATA drive, then I boot the computer. (Windows 7 64-bit) When it reaches the Windows logo/loading screen, it stays there. I have to hard reset my computer (and unplug the eSATA drive) and then it fails to boot correctly, Windows goes into self repair/restore mode. After a while it boots. As far as AHCI, I don't see a way of setting up RAID while using that setting. I can use my drives separately, but that is not possible in my current setup. (I may never use RAID ever again after this, unless parity is absolutely necessary). Also I would think the eSATA drive would show up on the boot order list since all my other SATA devices did; however, the external drive did not appear on the BIOS boot order list. My solution right now is to try an eSATA Express Card adapter, which should work completely separate from my internal SATA controller and AHCI stuff. That's it for now but I will most likely add my progress to this post regardless. Thank you for reading.