Arch Memory 1 GB (1 x 1 GB) 240-Pin DDR2 UDIMM for HP Pavilion a6220n RAM Arch Memory is a Registered Trademark of Arch Computer, LLC 1GB 240-Pin DDR2 800Mhz SDRAM Compatible with systems that use 240Pin PC-6400 SDRAM modules 1 GB Memory for HP Pavilion a6220n By Arch Memory Lifetime Warranty