It was announced in 1982 as the "cleaned up" successor to the 1975 Cray-1, and was the world's fastest computer from 1983 to 1985 with a quad-processor system performance of 800 MFLOPS.

The X-MP's main improvement over the Cray-1 was that it was a shared-memory parallel vector processor, the first such computer from Cray Research.

The X-MP CPU had a faster 9.5 nanosecond clock cycle (105 MHz), compared to 12.5 ns for the Cray-1A.

It was built from bipolar gate-array integrated circuits containing 16 emitter-coupled logic gates each.

In 1984, improved models of the X-MP were announced, consisting of one, two, and four-processor systems with 4 and 8 million word configurations.

[5] The CPUs in these models introduced vector gather/scatter memory reference instructions to the product line.

The amount of main memory supported was increased to a maximum of 16 million words, depending on the model.

For compatibility with existing software written for the Cray-1 and older X-MP models, 24-bit addressing was also supported.