An 11/23 is slower than a 486 if it's running faster than 16mhz. but a 486 is running single user. what is a PDP? choices 1,4,5,6,7,8,9,10,11,11/780,11/750,11/730? Depending... first I've rarely seen a vax run a single user OS. A 486dx/33 compares to a 3100m38 if they are both running *nix. while the vax is slower in MIPs it is the ultimate CISC and can do more in fewer than a 486. It is also optimized for multitasking/timsharing something the 486 is not. Allison