64kx1 DRAM, 10 pieces, 7 OKI M3764A-12 120ns, 3 Hyundai HY5164S-15 150ns, 16-pin DIP.

Hyundai was the brand name when they were manufactured. Then became Hynix, then SK Hynix.

To the best of my knowledge, these have never been used. They were left over from large sleaves of DRAM chips purchased in the 1980's to fully populate the memory in IBM PCs.