Raspberry Pi 400 Gets an 8GB Upgrade — By Hand-Balling and Soldering a Donor RAM Chip - Hackster.io
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Amazon.com: Vemico Raspberry Pi 4 Model B 4GB Set RAM 4GB Base Starter Kit with SD Card, Heatsinks, HDMI Cable, Power Supply, Black Case, Reading Card Device, Screwdriver : Everything Else
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