iPhone Logic Board
Matching the right iPhone logic board replacement for your iPhone involves knowing some key points. These are very basic but important nonetheless. Know the model of your iPhone and the size (capacity) as well.
Match the Size of the iPhone Logic Board
Keep in mind the service provider (carrier) but also note that there are unlocked iPhone logic boards as well as jailbroken. Firmware and operating systems can be updated. Many of these iPhone logic boards have been tested (connection ring, IC chips, Wi-Fi levels, etc.). On many of the boards you can tell the condition concerning water damage (one of the more common issues with iPhone logic boards) by checking the liquid contact indicators. The color should still be white indicating there have been no issues in this regard. See the description for the specifics on the condition of the iPhone logic board.
Logic3 Power Sleeve for iPhone 4 Black Wireless Phone Accessory
iPhone 3G Compatible Logic Board 1 MB