Has it been X-Clamped? Cause 0020 is generally a pressure on GPU issue. However I'd recommend trying to reflow, since it's whats fixed one of my 0020'ed consoles
Im in the process of an oven bake, on a board with 0020, I will post results.
Although if you think the board may be flexed I would reccomend an oven bake (Espically after a reflow/X-Clamp fix) as it will set the board straight
Check this out:
Code:
http://xbox-experts.co.uk/tutorial/oven-bake/
Didn't effect the error code, but I now have a moisture free unflexed board . It should now be easier to fix.