tout est dans le titre
je m y connais pas trop donc ce serait bien de decortiquer chaque etape
merci

Bonjour,
 
A mon avis, ce n'est plus possible.  
Il faut activer AHCI dans le bios, avant d'installer quoi que ce soit.
 
 
@

J'ai trouvé une procédure pour activer AHCI aprés installation XP avec mode bios IDE.  
Pour moi ça a marché nickel (carte mère ConRoeXFire-eSATA2 ich7r)
Ca évite de réintsaller XP avec le F6 et la p'tit disquette.
Y'a pas pour southbridge ICH8 par contre
 
 
source http://www.neowin.net/forum/index. [...] 57699&st=0
le contenu
Some of you might know that AHCI enables Native Command Queuing support and Hot Plugging for SATA drives. Unfortunately it can usually be enabled only when installing Windows, by using a floppy drive.
 
Spported southbridges: ICH6R, ICH6M, ICH7R, ICH7DH, ICH7M
 
Instructions:
1) Make sure AHCI is not enabled in your BIOS, otherwise this guide is pointless for you.
2) Back up your Windows folder and prepare a boot disk in case this guide fails!
3) Download 79im05ww.exe from http://www-307.ibm.com/pc/support/ [...] MIGR-62909
4) Extract the file to C:\DRIVERS\WIN\SATA.
5) If you have the ICH7M southbridge, go to step 8.
5) Open C:\DRIVERS\WIN\SATA\PREPARE\IMSM_PRE.inf in Notepad.
6) Replace any instance of DEV_27C5 with the following, according to your southbridge:
ICH6R - DEV_2652
ICH6M - DEV_2653
ICH7R - DEV_27C1
ICH7DH - DEV_27C1
ICH7M - DEV_27C5
7) Save the file and close Notepad.
8) Click Start, select Run.
9) In the Open field type C:\DRIVERS\WIN\SATA\PREPARE\INSTALL.CMD and click OK.
10) Restart your computer, and enable AHCI on in your BIOS Setup.
11) Start Windows XP or Windows 2000. The Found New Hardware wizard will start automatically.
12) If running Windows XP:
 
1. Click No, not this time then click Next.
2. Select Install from a list or specific location (Advanced), then click Next.
3. Select Search for the best driver in these locations.
4. Select Include this location in the search: and specify the path, C:\DRIVERS\WIN\SATA, and click Next.
 
13) If running Windows 2000:
 
1. Click Next.
2. Select Search for a suitable driver for my device (recommended), then click Next.
3. Select Specify a location, then click Next.
4. Specify the path, C:\DRIVERS\WIN\SATA, and click OK, then click Next.
 
14) Click Finish.
15) When the System Settings Change window appears, click Yes. The computer restarts.
 

Franchement tu m'as sauvé la vie !
NB: joams, mets RESOLU dans l'entete du sujet