Patriot Viper Elite II DDR4 8GB(1 x 8GB) 4000MHz Single Memory Module at Amazon.com
Thermaltake TOUGHRAM RGB White DDR4 4000MHz 16GB (8GB x 2) 16.8 Million Color RGB Alexa/Razer Chroma/5V Motherboard Syncable RGB Memory R022D408GX2-4000C19A at Amazon.com