3ware 7506-8 disk issues

[W. Desjardins]

All...

I have a system with a 3ware 7506-8 controller and 6 wd 250MB drives in a
raid 5 config (1.2TB storage). The problem I am having is trying to
configure the raid 5 array as a disk. using sysinstall, I get this message
with every fdisk key press:

'a geometry of 152005/255/63 for twed0 is incorrect'

from there it drops me to the fdisk window and using 'a' for the entire
disk, gives me this geometry which is invalid

offset	size	end
0	63	62
63	2441960262	2441960324
-1853006971	14715	2441975039

first, that seems very wrong, but I leave fdisk anyway. when I go into
disklabel, I get an error stating:

Fatal Error: Partitions are larger than actual chunk?? - PRESS ANY KEY TO
QUIT

so, I can not create that disk. I am running 4.9 with the latest 3ware
drivers compiled in. 3ware specifies to use 4.8 with their drivers, but I
get the exact same err on 4.8.

I am not as adept to on the cli setting up the disk, but everything I try
fails. I think I could get it working with the right geometry, but I am not
sure how to even get that.

questions....

can the twe driver support this config? how can I detect the actual geometry
of the raid5 disk? what steps are needed to setup the disk?

At this point, I am at a loss on this, so any suggestions or help is
appreciated.

Also...I have followed the handbook and any other doc I can research on the
website, google and  anywhere else with no avail...

TIA,

Bill