You are probably overestimating the Cray, modern CPU's have a lot of bandwidth. And due to being physically smaller fewer issues with latency, and fairly large on chip cache.
Someone did the math and a Cray was on par with an intel core i3 series (early gen) in sustained perf even though in terms of raw GFLOPS the intel cpu was two leagues above. That's all I'm saying.
That's not a Crey 2. That is talking about the X-MP it's successor.
https://en.m.wikipedia.org/wiki/Cray_X-MP "The Cray-2, a completely new design, was introduced 1985. A very different compact four-processor design with from 64 MW (megaword) to 512 MW (512 MB to 4 GB) of main memory, it was specified to 500 MFLOPS but was slower than the X-MP on certain calculations due to its high memory latency.
The X-MP-succeeding Cray Y-MP series was announced in 1988; it also had a new design, replacing the 16-gate ECL gate arrays with a more compact VLSI gate array with larger circuit boards. It was a major improvement of the X-MP supporting up to eight processors."
Note latency is huge for these systems meaning for most workloads modern cellphones absolutely crush them.
I'll link the url when I've scanned my bookmarks.
psedit: look at jojomonkeyboy's comment http://www.techrepublic.com/blog/classics-rock/the-80s-super... he says an i7 2600 (not an i3) has less sustained compute power.