The XMP evolved from the Cray 1 and introduced dual processing to the Vector line. Originally limited to 16 MWd memory the later "Extended memory architecture" variants grew the address register from 24 to 32 bits growing the maximum program size to 2 GBytes. The XMP was brought to market whilst the Cray 2 was still in development and was a huge success that proved hard to repeat in later years. The line of big-iron vector super computers continued with the YMP, C90 and T90 each generation of which approximately doubled the CPU speed, number of CPUs, memory size and CPU quantity along with improving a host of other details.

Date| Model| | Max. Number CPUs CPU speed per CPU approx. peak.1976 C1 1 0.160 GFlop1982 XMP 4 0.235 GFlop1988 YMP 8 0.333 GFlop1991 C90 16 1 GFlop1995 T90 32 2 GFlop

The YMP range of machines started by utilising new board and cooling technology for just the CPUs, using XMP style boards for the IOS and SSD. Eventually the IOS and SSD also came to use YMP style, internally cooled boards in a range of chassis sizes. This final leg, which balanced the extreme performance of the memory and CPUs, was the model E IO subsystems which provided high speed sustained and parallel input/output capacity for the system.

The YMP and C90 ranges were both available in a number of chassis combinations which determined the maximum memory, SSD size and number of IO subsystems. The smaller 2..4 CPU chassis YMP model Es were (later) available with air secondary cooling as an option.

The introduction of the C90 brought the first Gigaflop per CPU systems to the range in 2,4,8 and 16 CPU chassis sizes.

The YMP and C90 families both had later variants which offered to replace fast memories with extra large DRAM memories.

The T90, available with up to 32 CPUs, harked back to earlier days with its use of total immersion cooling but in another way forged ahead with its replacement of the traditional wiring mat with special board edge connectors.

Only in a Wiki could you attempt to represent Super computer internal technology in 5 lines of ASCII so here goes ....

Boot ---- IOSs -- Disks, tapes, networks etc.

Device / | | \ Side door OWS

CPUs--SSD large attached memory, optional.

Vhisp channelsBack door

Memory

The thing to remember when looking at this is that there are multiple paths between everything and within everything that could all work at once.