HP XW8400 DAE error -1115 was encountered

[jyt]

Hi here is my setup

HP XW8400 -windows 7 64bits- sas drive-8GB of ram
two core card pci-x
one accel pci-x

I get this DAE error -1115 was encountered message as soon as I put
core in pci slot 5 133mhz
core in pci slot 6 100mhz
accel in pci slot 7 100mhz

if I remove core in slot 6 and replace with accel, it's all good
just the two core is also working
if i skip slot 5, then i get the error

my conclusion, is if i trade one core for an other accel card, am I going to run into the same problem, does core-accel-accel run on an xw8400

anyone please!