The C-class workstations are single processor workstations which have less expansion (CPU, memory and I/O) when compared with the j-class. The Model C3600 uses a 400MHz PA-8600 processor and includes 512KB of instruction and 1MB of data cache. The unit can support two internal disk drives equating to a 72GB maximum when configured with 2 x 36GB drives. It also supports from 512MB through to 8GB of memory.