AHCI with multiple partitions?

My system was/is running XP Pro 32-bit.

Just installed Windows 7 Professional 64. Installation went fine. Cleared partition C and did a regular install.

BUT, I'd like to turn on AHCI, which I found instructions for, so I'm up for giving that a try. My concern is the other partitions on the boot drive. Windows 7 is in C, my installation of XP is on D, and I've got a bunch of other stuff in a third partition......

If I go through the process of getting AHCI working on this disk will it have any impact on my other partitions?


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I don't think it would mess up the other partitions, but don't know for sure. Back it up just in case.

If you already have the OS installed, you will need to do a registry hack before you change to ACHI. If you don't your system will not boot.

I tried ACHI once. Because it is not a large improvment plus the drives were always shown as removable devices, I changed back to IDE.

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I backed up everything, so I"ll give it a try after lunch... I've seen various claims for "significant" performance improvements to "NO" performance improvements, but since I've got 5, 1TB drives on here, it'd be nice to get significantly more performance than the approximately 25MB/sec I get now...

Turned on AHCI. For me, it's made a huge difference in disk throughput....... On a disk-to-disk copy I was getting approximately 24.6 MB/sec. Now I'm getting between 52 and 56 MB/sec.

Backups (which are also disk-to-disk) using Syncback are also significantly faster.

I haven't seen any problems...................... YET.

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