SH-S203B and JMicron BIOS settings

one simple question:

which mode for my JMicron SATA2 controler should I use in BIOS: IDE or AHCI ?


Gigabyte GA-P35-DS4 rev 1.1 BIOS F7
Samsung SH-S203B


Simple answer: IDE.


can you tell me what is the advantage of IDE mode?
(I see that S203B reads without problem in both IDE and AHCI mode - haven’t tried writing yet…)

It works for me in AHCI mode. I’m using the drivers from Jmicron’s site.


It is the most compatible operation mode provided, MS standard drivers are used.

(I see that S203B reads without problem in both IDE and AHCI mode - haven’t tried writing yet…)
In AHCI mode you have to rely on the drivers from the manufacturer. A newer version might cause issues (or not). Also, you can’t install Windows from a drive connected to an AHCI controller (unless you provide a driver floppy).


I cannot load windowz (XP Pro) when using AHCI (Asus P5B Deluxe). I have to use IDE but it could be all the drives i have hooked up?

You have to have the ahci driver installed in xp in order to boot in ahci mode. I had the same issue recently when i set the intel controller in ahci mode from bios (I, too, own a p5b deluxe), and the solution was to repair the installation using the windows xp cd and a floppy with intel’s ahci driver.

Thanks for the info. Am i really loosing out though?

afaik, ahci is needed for full sata II support(hot-plugging, NCQ, 3Gb/s transfer rate). But then, NCQ is not so useful in single user pc’s unless there is too much load(lots of reads/writes) plus your disk might not even support NCQ. As for the transfer rate, sataI(1.5Gb/s) provides more than enough bandwidth for today’s hdd’s(WD raptors use sata I, still they’re the fastest sata disks in the market). So I don’t think you actually need ahci, ide mode works just fine.

Lightning said he never could get the jmicron chipset to work worth a darn in his testing. His advise is use a controller card or another chipset

Thanks again. Looks like a later dated upgrade for me anyways. IDE is fine for me at this time.

I guess I am pretty lucky then… I have had decent luck with the onboard Jmircon controller (both ACHI mode and IDE mode) using ImgBurn. I have an Asus P5B Deluxe WiFi/AP and use the Jmicron eSATA port for connecting a Samsung SH-S203B and LG GSA-H62N. But I admit, I’m not a big fan of Jmicron.