Startup problem: sda/sde

[Pol Hallen <debianen@fuckaround.org>]

Hi folks :-)

I've asus P5B-E motherboard with debian stable.

First 6disks (integrated controller: sata1-sata6) for raid (not implemented 
yet) and boot disk (integrated sata7).

The problem is: sometimes debian probe boot disk (sata7) on sda and the boot 
process is ok (lvm encrypt ask to me the password) , but often debian probe 
boot disk on sde and the startup stop :-////

In the bios of mb I see an option like this: "allow bios discover device - 
allow os discover device".

I tried both but I've the same.. enervating.. problem..

Can I will do?!

Thanks! 
Pol