MrTea > I loaded the drivers in the beggining of the setup (in fact I'd slipstreamed them)...

Last time I tried to install XP I got the message "NTLDR is missing" after the first setup reboot

<{POST_SNAPBACK}>

XP does not recognize SATA raid features on most motherboards, since XP needs 3rd party drivers to point to these devices.

Even though you may have installed an OS on a drive and the device drivers does not guarantee that it will boot. Most occurances of 'NTDLR is missing' with 3rd party controllers is that the specific device is not enabled in the bios. Are you sure you installed the OS on the appropriate drive?

I use the same 3112r (silicon image).

Setup raid to either strip(0) or mirror (1)

Raid0 (strip) Will combine the two drives but you will only see about 70-80% of your physical drive space.

Raid1 (mirror) will combine the two drives, copies the image off primary disk (redundent setup), you will be utilizing around 70-80% of the 400gb but the OS will only notice 200gb.

hm... but the setup don't show those two options, it only shows "Silicon Image SiI 3112 SATARaid Controller"...