I asked one of the old IBMers at work what this powerstation 550e i had was. turns out it is indeed part of the RISC6000 family. I guess what i have is just a workstation that ran batch jobs or something like that, not too useful by itself it seems. I presume it runs/ran AIX. it was difficult to find any info it. web search didnt bring up anything, and 800-IBM-SERV handles the RISC6K family, but they referred me elsewhere for this 550e, since they didnt know what it was. it only cost $5, and it is an interesting addtion to my ever growing esoteric collection of ibm machines. now, if i could just get this powerstation to run with my PC RT... david