A forum post at Chinese site WeiPhone offers a photo of what is claimed to be the iPad 3's logic board showing an "A5X" system-on-a-chip.

Jobs Mob had been promising an upgraded processor and graphics package for the iPad 3, and everyone thought it would be an A6 chip after the A5 was jacked under the bonnet of the iPad 2 and iPhone 4S. If the snap is correct then it means that Apple is carrying on its tradition of doing slight improvements to its products and hope that people are dumb enough to buy it.  Fortunately its business model of depending on customers not seeing through this cunning plan and shouting down those who say that the emperor has no clothes has worked well.

A date code of "1146" on the A5X indicates that it was manufactured in the 46th week of 2011, which would have corresponded to November 14-20. This means that the "A5X" as a step-wise upgrade to the A5 corresponds with progression of processor part numbers as revealed by BGR in February. At the time the A4 was known to be the S5L8930X, the A5 as the S5L8940X and the new iPad processor as S5L8945X.

Several other features are also visible on the logic board, including a pair of 16 GB flash memory chips from Hynix and a rectangular Apple-branded chip. That chip appears to correspond to power management chips found in previous iPad teardowns although it might have been slightly upgraded.

Apple is expected to introduce the iPad 3 at a media event on March 7, with the device also receiving an ultra high-resolution display and LTE capabilities.