Compaq Computer Corp yesterday came out with repackaged models of its ProLiant servers that come rack-mounted to appeal to mainframe users. The new rack-mountable servers come in two sizes – a four foot high rack holding up to three ProLiant 1000R, 2000R or 4000R servers, and a seven foot high rack that can hold up to six ProLiant servers. Each 80486 or Pentium-based server in a rack will run independently, but a fully configured rack installed with up to six ProLiant 4000s will have enough power to drive thousands of desktop computers. Prices for the new rack-mountable servers will start at under $6,000 for the 80486DX2/66-based ProLiant 1000R. A switchbox will enable a single keyboard, monitor and mouse to control and monitor up to eight servers.