ASUS P5Q - very strange problem...

Hi,

I very strange problem with Asus P5Q. I have Raid 0 (2x WD 320 GB SATA), 1 DVD SATA and 1 CDRW PATA.
When I set SATA to RAID and disable Marvell IDE, I can’t boot from SATA DVD (that is first device to boot from). It seems to spin up DVD when It should but nothing else. When I enable Marvell IDE, set first boot device to PATA CDRW and (strange here) press ANY KEY (let say M letter key , no matter what key it will be) on POST screen its boots from PATA CDRW. It allowed me to install XP from PATA CDRW on RAID0 and it works well - BUT I have to press ANY KEY on POST screen each time to make boot from RAID or CDRW possible. If I disable Marvell IDE (having installed XP on RAID) it says that there is no system Installed and not even try to boot from RAID unless… I enter BIOS setup and close it without changing anything… after that it boots from RAID…
That’s crazy… does anybody knows what to do?
Ergen