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16GB Memory RAM Compatible for ASUS ASUS Notebooks X541UJ,X541UVK,X542URR,X550IK,X550IU,X550VXK,X555BA,X555QA,X556UA (DDR4),X556UAK (DDR4) - Walmart.com
OFFTEK 8GB Replacement Memory RAM Upgrade for Asus X556UA (DDR3-12800) Laptop Memory at Amazon.com
Asus Laptop RAM X556UA | Official Asus Partner - Asus Accessories