Every now and then I will get a chip in that I cannot ID. This is a particularly perplexing one. It looks like it should be something fairly well known, but I cannot determine what. By the dates its a 2005 vintage IBM, MCM, on a fairly large ceramic package with 1077 lands. It contains a pair of Infineon HYB39S256160DT-7 256Mbit (4Mbitx16bit) DRAMs which are 7ns 143MHz max, commonly used on PC133 SDRAM. That works out to 64MB. Also on the package is a IBM0436A8ACLAB 8Mbit (256Kx36) 4.5ns (222MHz) 1Mbyte SRAM.
Markings on the die are:
If you have any ideas what it is, or what it may be, post a comment. I may just give you one. These came in with a lot of HP PA-RISC processors, so perhaps related?
UPDATE (10/20/2016): Mystery solved. These are processors from a Cadence Palladium emulator system. Read more about them here