FreeBSD Geometry Error

While I was installing FreeBSD 6.2 I received the error "a 
geometry of 29437/16/255 is wrong, using a more likely 
geometry" at this point I would usually just continue the install 
with no problems as it auto detected the correct geometry but for 
some reason it didn't work this time. I was getting errors 
afterwards such as "unable to write data to disk ad1" when it was 
time to install.

I tried entering the geometry my BIOS reported and this also 
didn't work.

The fix was this:

I had to do the install from Safe Mode. After the install from 
Safe Mode I also had to boot into the new install using Safe 
Mode and add the following line to the bottom of the 
/boot/loader.conf file:

hw.ata.ata_dma=0

This disabled DMA and now the system will boot normal.