The agreement that Amdahl Corp would use the Encore Computer Corp Infinity 90 RISC-based storage array as its contender for the disk subsystem market addressed by IBM Corp with its Ramac arrays, has fallen apart. The agreement was first announced last spring, but by autumn had already been amended, and the two now say they were unable to reach a final, definitive agreement resolving their differences over the reseller agreement. Amdahl had sued to block Encore from ending the agreement. It now says it remains fully committed to delivering a RAID disk array for its System 390 customers in the second half of the year.It is possible that the company may try to do a deal with Data General Corp on adapting CLARiiON disk arrays for mainframes.