Cant remove raid from Hard drive

[Robert]

Greetings

I am trying to reuse a 500G harddrive that was previously part of an
NVIDIA raid in a windows box.

I have tried to clean the disk using "dd if=/dev/zero of=/dev/raid/r0
bs=1m". The dd program completed but the raid info is still on the disk,
I was able to set up the disk with 

gpart create -s gpt /dev/raid/r0
gpart add -t freebsd-ufs -l 500Gig -b 1M
newfs -U /dev/gpt/500Gig

I can mount and use the disk but it still shows up at /dev/raid/r0 and
my dmesg is spammed with

GEOM_RAID: NVIDIA-1: Array NVIDIA-1 created.
Root mount waiting for: GRAID-NVIDIA
Root mount waiting for: GRAID-NVIDIA
Root mount waiting for: GRAID-NVIDIA
Root mount waiting for: GRAID-NVIDIA
Root mount waiting for: GRAID-NVIDIA
Root mount waiting for: GRAID-NVIDIA

until it times out or I hit ^c

 uname -a
FreeBSD zorro.shasta204.local 9.1-STABLE FreeBSD 9.1-STABLE #1 r246453:
Thu Feb  7 11:52:20 PST 2013
root at zorro.shasta204.local:/usr/obj/usr/src/sys/GENERIC  amd64

Any help greatly appreciated.

Robert