I have two WD250's that I just finished running 3 cycles of preclear on.  I noticed after I started the preclear that the syslog showed them as both having hpa.

 

Once the preclear's finished, I tried the command hparm -N pXXXXXX /dev/sdX

 

I get an error about buggy drivers.

 

Next I took my dos bootable flash drive, and put HDAT2 on it, booted and ran HDAT2.  This comes up and only seems to recognize 4 of the 6 drives in the server. the last two (WD 250's) show up as BIOS devices.

 

Whats my next step?

 

Try putting those two 250's into the first 4 slots rather than the last 2.  Chances are HDAT2 can't access the last 2 ports while they are in AHCI mode.

This worked!

 

I was able to remove the HPA partition!

 

Thanks