fpg, XT4 is the platform that will accept, in S1207 sockets: A) Opterons, B) DRC's Xilinx-based FPGA copro's, C) Cray's custom Threadstorm multithreaded (128 threads) processors. D) Various mixes of the above. You are right. I wasn't sure about c) but this interview posted and highlighted by Robert G: <A HREF="http://www.siliconinvestor.com/readmsg.aspx?msgid=23010145&srchtxt=cray" target="_blank">http://www.siliconinvestor.com/readmsg.aspx?msgid=23010145&srchtxt=cray</A> confirms it Original link: <A HREF="http://www.hpcwire.com/hpc/1086098.html" target="_blank">http://www.hpcwire.com/hpc/1086098.html</A> Very smart approach by Cray, it seems. Joe