Its enabled, but with few limits. At stock, its only enabled when you boot with 200FSB. If you boot with 201FSB, PAT will be disabled. ´

Few tricks to enable PAT over 200FSB:

Boot up with 200FSB, and raise fsb from windows with Clockgen or SetFSB.

Or

You can flash P4P8X board bootblock and have PAT with any fsb.
After this mod, you will loose 5:4 divider until you flash orginal P4P800 bootblock back. Use search for further information.