I forgot to tell that there is a wire to be added :
IRQ from HDD
Solder the wire on the right top corner of the CTPCI (pad is here for that).
And the other end of wire must be connected on IRQ on MB.
You have choice : pin /wire #31 of the primary IDE Port/flat cable
or solder on pin #1 of the U25 chip (74HCT04), under CT60 near Zilog.
It seems that some ATA commands like DEVICE IDENTIFY use the IRQ from HDD.
It is on CT60 boot only !
After, as far as I saw, the IRQ is never used.