AHCI or IDE

nheather · 23 Jan 2010 at 22:58

For a Windows 7 installation with individual disks would you recommend using AHCI?

Four disks in total - 2x SATA HDD, 1x SATA DVDRW and 1x PATA DVD

Would your answer be the same if the install was dual boot Win7 and WinXP?

What if I added a Linux boot aswell?

I've read about AHCI as much as I understand and I gather it gives a slight improvment in performance, noise and energy over IDE.

I'm also aware that XP doesn't have built in AHCI drivers so you need to add these at install.

I'm tempted to go AHCI but if it is going to be a headache then I would be convinced otherwise.

Many thanks for your help.

Nigel

AbsenceJam · 24 Jan 2010 at 13:26

Only reason to use AHCI is if you have an SSD and it needs to be in that mode for TRIM to work. There's NO advantage otherwise.

nheather · 24 Jan 2010 at 16:18

Many thanks,

Advantages as far as I can see are

(i) Performance - but really only makes a difference in a server like environment (lots of multi-threading)

(ii) Hot Swap Drives - so you could use an eSATA like a USB drive

Disadvantages

(i) Slower Boot - as AHCI drivers are loaded

(ii) Installation Hassle - for example XP and possibly Linux

(iii) Performance Hit - some have reported a performance hit for single threaded apps

Performance improvement (if any) is small so not really bothered by that.

I do like the eSATA option, but I guess I still have it as long as I plug\unplug whilst the PC is off - no big hardship

I don't like the slower boot

So I'm leaning towards leaving everyting as IDE.

Cheers,

Nigel

AbsenceJam · 24 Jan 2010 at 17:24

There's no performance difference unless you then enable NCQ, then performance is worse.

You can hotswap in IDE mode, in AHCI mode the drives are just picked up automatically.

Threads is the number of processes a program uses, nothing to do with disk I/O.