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 # Lenovo T420
 
 ## Flashing instructions
-You have to disassemble the whole device, as the flash IC is on the bottom
-of the mainboard.
+The flash IC is located at the bottom center of the mainboard.  Sadly,
+access to the IC is blocked by the magnesum frame, so you need to disassemble
+the entire laptop and remove the mainboard.
+
+Below is a picture of IC on the mainboard, with the pinouts labeled.
+
+[t420_chip_location]: t420_chip_location.jpg
+
+The chip will either be a Macronix MX25L6404E (shown above) or a Winbond
+W25Q64CVSIG.  Do not rely on dots painted in the corner of the chip (such as
+the blue dot pictured) to orient the pins!
 
 For more details have a look at [T420 / T520 / X220 / T420s / W520 common] and
 
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