How much stronger would Mephisto uci engines be than before?

[JohnW]

I have downloaded several uci engines of the old Mephisto chess computers like

Mephisto Amsterdam
Mephisto Dallas 32 bit
Mephisto Gideon Pro
Mephisto Roma

Since running them on my i7-6700K cpu is quite a bit better than the hardware they originally ran on, how can I calculate what there rating would be?
The only engines they can compete with are themselves, anything modern and they lose. So I wasn't sure how to go about calculating their rating. Any advice would be appreciated. Thank you..

[Werewolf]

I have downloaded several uci engines of the old Mephisto chess computers like

Mephisto Amsterdam
Mephisto Dallas 32 bit
Mephisto Gideon Pro
Mephisto Roma

Since running them on my i7-6700K cpu is quite a bit better than the hardware they originally ran on,

Understatement of the century.

If you allow 40 elo per doubling of speed, which I think was applicable for those programs back then, that's a starting point.

The next task is to work out how much faster your current CPU is per clock cycle c/p a 68000 etc. And of course the 68000 ran at 12 MHz whereas your machine is 4.2 GHz.

So,
4200/12 = 350

Then allowing for instructions per clock cycle increase...say 5x (I have NO idea) = 1750 times faster!

Now see how many doublings go into 1750, which is
2,4,8,16,32,64,256,512,1024,2048 - ROUGHLY 10.

So 10 x 40 = 400 elo better.

That's dog rough, but it's probably in the right ball park.

[hgm]

Not sure what you mean by "The only engines they can compete with are themselves"? Does that apply to the UCI versions or the original hardware? Surely the UCI versions can be handicapped by time odds such that they perform as the original hardware. And then they can be played against any engine. I am sure there must be hundreds of engines that are far weaker than them. You could start with something that is around 500 Elo on CCRL...

[Graham Banks]

I have downloaded several uci engines of the old Mephisto chess computers like

Mephisto Amsterdam
Mephisto Dallas 32 bit
Mephisto Gideon Pro
Mephisto Roma

Since running them on my i7-6700K cpu is quite a bit better than the hardware they originally ran on, how can I calculate what there rating would be?
The only engines they can compete with are themselves, anything modern and they lose. So I wasn't sure how to go about calculating their rating. Any advice would be appreciated. Thank you..

Mephisto Gideon Professional is rated 2477 in the CCRL 40/4 list.