Anandtech has excellent, in-depth articles about electornics hardware. The site doesn't disappoint with its latest analysis of the iPad breakdown from iFixit. They point out subtle differences between the iPad 2 and the iPad 3 including Apple's possible move to a flip-chip design with the A5X, which allows for better removal of heat. If you're into DRAM, NAND and SOC, then you should head over to Anandtech for the rest of the details.