Is it possible to compare a present day PC to a "supercomputer" from years back?

Factual Questions
1

If so, how far back do we have to go to say we have roughly to power of a Cray sitting on our desk now?

Lets say someone has a relatively high-end modern PC, for example, a Pentium 4 2.8Ghz or 3Ghz with a boatload of RAM, say 1GB. Would a Cray of say, circa 1990 be more powerful than that?

Forgive me if I can’t be more specific for labeling a particular supercomputer, I’m not very familiar with them but I was curious if a person could “ballpark” how far we’ve come with desktop power.

2

Are today’s PCs more powerful than the legendary supercomputers of the 1970s?

3

Thanks for the link. While a recent article, (very recent!) the computer it is quoting is “relatively” old now… but it does give an idea.