As you might recall, the only cards in the R9 300 family to use AMD's current-generation Tonga GPU are the Radeon R9 285 and R9 380, meaning they are built on a 28nm manufacturing process and use AMD's GCN 1.2 architecture.
ຕາມທີ່ທ່ານຈື່, ບັດພຽງແຕ່ໃນຄອບຄົວ R9 300 ທີ່ໃຊ້ Tonga GPU ລຸ້ນ AMD ລຸ້ນປັດຈຸບັນແມ່ນ Radeon R9 285 ແລະ R9 380, ເຊິ່ງກໍ່ສ້າງໃນຂະບວນການຜະລິດ 28nm ແລະໃຊ້ສະຖາປັດຕະຍະ ກໍາ AMD's GCN 1.2.