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i5-3380M @ 2.90 GHz CPU, 16 GB DDR3 RAM, 12.5" IPS 1366x768, 9-cell aftermarket battery from KingSener. Around €80 for the base system + dock, plus €35 for the RAM and €35-40 for the battery.
Can charge from a 65 W USB-C power supply through a cheap (~€5) USB-C to 7.9 x 5.5 mm adapter.