8GB Raspberry Pi 4 on sale now at $75 - Raspberry Pi
Setting Up a RAM Disk on a Raspberry Pi 4 - YouTube
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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 : Electronics
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Raspberry Pi 4, Now With Upgraded RAM & A New Price Point!
Amazon.com: RasTech Raspberry Pi 4 8GB Starter Kit with 32GB Micro SD Card, Power Supply with ON/Off, Case, Cooling Fan, HDMI Cable, Card Reader, Copper Heatsink, Screwdriver : Electronics
YouTuber Upgrades Lowest Spec Raspberry Pi 4 to 8GB of RAM | Tom's Hardware