It seems that Atari PSUs are subject to the same issues that some Commodore PSUs are - namely that the voltage they put out can increase with age and damage the motherboard.
Is anybody aware of either a supplier of new XL/XE compatible PSUs or at least a protection device similar to what is available for the C64?
http://www.lemon64.com/forum/viewtopic.php?t=61438&sid=4a02722ad35fd97044b2a8fbbf4bdb82
Any info would be very welcome as one of my PSUs failed and took a perfectly good 800XL with it