I have delidded all my socket 478 P4s The 533 bus northwoods are only held on with TIM all the rest are soldered.
Its pretty easy to do just cut around the edge with a single sided razor blade then insert 2 blades on opposite sides. I use a hot air rework station to heat them up.
Then I pare the excess solder off the top of the die with the blade I usually rub the blade (just a couple of strokes) with a worn out piece of 1500 that I have used for lapping to ensure there is no burrs on the edge. You can see spots where the solder hasnt actually stuck to the top of the die on some of them one had about a third of the die that wasnt properly adhered to the solder .Then I just give the die a couple of strokes with the worn out paper.
You know me Shrimp I delidded my I7 3770 before I even ran it But its only held on by TIM , Bugger the warranty
When I get a cheap 2600K to bench I will delid that without any quarms.
Its good to know that with the FX the glue is actually between the resistors that would make it a bit more tricky.
Here is a couple of pics of my P4s
Edit: The pics are not that good the tops of the dies looks a lot better in real life
http://www.overclockaholics.com/foru...1&d=1363084314
http://www.overclockaholics.com/foru...1&d=1363084314