DISC0 not detected

Hello everyone

Another Problem I have since the beginning of my Vista x64 Installation as second OS for my Dual Boot.

XP Pro works fine since the beginning and once in XP I can see either in Explorer and Device Manager and Administration Tools both of my HDD

Vista only detect one the one on which it is installed (second HDD DICS1)

I tried rescan in administration Tools no results.

All Boot File are on DISC0 (the one Vista does not recognize)

Any solution? I'd like to use EasyBCD but if Vista does not see the HDD with the Boot file on I almost sure I won''t be able to use EASYBCD under Vista.

Also When I restart my PC from Vista, BIOS does not detect anymore my DISC0, so I get a BOOT file not found and have to switch off completly and switch on again and BIOS is normal.
I think one problem is related to the other.

Thks in advance for your suggestions