What was your old Motherboard make/model?
You need to enable RAID in the BIOS you do not need to enter the RAID BIOS the screen as it boots up should show your array.
If you have done this try other ports.
Note: if an OS was installed on this RAID it may not boot into windows but your data will be fine.
whoops I just found out that I did NOT connect the hard drivers to the intel controller on my old mainboard but to some silicon image controller well I guess there is no chance to simply continue my old raid. But thank you anyway.