ddr4 slots backwards compatible: [How to Install or Add More RAM to Your Windows PC. PUT YOUR GPU IN THE TOP PCIE SLOT IMMEDIATLY. Mini PC Intel Core i7 10510U 2*DDR4 M.2 SSD NVMe Windows 10.
However, DDR4 RAM may not be backward compatible with DDR3
slots, so it’s essential to verify compatibility before purchasing.
It's worth noting that the PCIe standard is backwards compatible, so you can, for instance, use a PCI-e 4.0 graphics card in a PCI-e 3.0
slot without issue, although you will see a small performance hit.
Mini PC Intel Core i7 10510U 2*DDR4 M.2 SSD NVMe Windows 10 Linux Dual-Band WiFi HDMI-Compatible DP 4K 60Hz USB-C 1*Ethernet