IBM rolled out a mainframe last week that breaks the 16-processor barrier.Called the IBM eServer zSeries 990 and codenamed T-Rex, the mainframe is available with eight, 16, 24 or 32 processors and has almost three times the capacity of its predecessor, the z900. It doubles the number of logical partitions to 30 and raises the number of Channel Path Identifiers (CHPID) to 512. A CHPID is a channel type and includes ESCON, Fibre Channel and Open Systems Adapters (OSA).In addition, T-Rex has four times the number of HiperSockets for creating internal LANs. The z990 supports up to 16 internal LANs.It runs Linux and z\/VM operating systems.The z990 also has enhanced ESCON, FICON Express and OSA-Express and has improved its fiber-optic cabling services via IBM Networking Services. It can process more than 11,000 Secure Sockets Layer handshakes per second.The z990 has four times the memory (up to 256G bytes) of its predecessor and double the I\/O capacity (up to 96G bytes). In addition, the z990 offers On\/Off Capacity on Demand, which lets mainframe customers bring processing power online as needed.It uses a new multichip module processing engine design, which allows it to perform twice as fast as the z900.The first models of the z990 - the A09 and B16 - are expected to be available in June; the C24 and D32 are expected to be available in October.Pricing details are not available.