I had a audio PC built for me recently, and I just noticed that the hard drives are in IDE mode. From Googling everyone says that Windows 7 should use AHCI not IDE.
So, is there some reason specific to audio PC requirements that my PC would have been intentionally set to IDE, or should it infact be AHCI ?
From a quick look around AHCI only seems worth it if you plan on using an SSD drive.
This is not the right place. Hardware forum’s best or just google. Much quicker.
My info could be out of date. I’m only up on these things really when I’m building a new machine.
if you’re using windows 7 with current generation ( SATA not IDE) hard drives then yes, you should use AHCI.
Some first gen SSD’s strangely DO NOT use AHCI and must be used in IDE mode, OCZ for example.
MC
That’s what I thought: can’t understand why a specialist builder would have not enabled AHCI 
There’s no noticeable difference in real life, it just enables a few SATA specific advanced functions.
In any practical terms it won’t make a bit of difference to your computer.
From Intel’s website:
Advanced Host Controller Interface (AHCI) is an interface specification that allows the storage driver to enable advanced Serial ATA (SATA) features like Native Command Queuing and hot swap.
As Nigel from Spinal Tap said, it wont make any difference on windows, if you ever wanted to install OSX however (hackintosh)then you must have AHCI enabled.
MC