Increase in Elo ..Question For The Experts

[Steve B]

50*(log(866/66)/log(2)) = +175

60*(log(866/66)/log(2)) = +222


175 ... 222

It could be a bit more I think. From the SSDF list there is for instance Chess Genius 3.0 DOS with a rating of 2256
174 Genius 3.0 486/50-66 MHz 2256 24 -24 866 61% 2175
But the same program on a Pentium 90 MHZ was already
158 Genius 3.0 Pentium 90 MHz 2312 25 -24 824 60% 2240
If you'd speed up that Pentium 90 MHz to 866 MHz and assume an optimistic 70 elo increase per doubling (Rybka claims it gets 70 elo per doubling), I get about 228 elo increase over Pentium 90 MHz.

So assuming a Pentium III 866 MHZ is about a ten times faster Pentium 90. That would be an upper limit, but not so unrealistic; if it was a large program that would not fit in the cache of the 486,- I'm not sure, but I don't think the 486 actually had an on board/chip instruction cache?-, and knowing there are Pentium III 866 procesors with 256 kB L2 cache but there were also for instance the Celerons, that were Pentium IIIs but had IIRC only 128 kb L2 cache (I had one of those, 500 MHz Celeron Pentium III), but otherwise these were identical (Of the 866 Pentium III I think the 128 kB version was not called Celeron anymore). If this chessprogram would now fit completely in that 256 kB cache of a real Pentium III, and for an old program I think it might, then that would be beneficial to its execution speed, irrespective of the increased clock speed to 866 MHz. So with some luck I think you would get more that figure of +222 that you get from just looking at the increased clock speed.

Eelco

Hi Eelco
interesting you sohuld use Chess Genius as an example because it is Chess Genius that i am asking about


Specifically
the Wiki shows an estimated rating for the WunderMachine of 2350..
this was for a WM with a 486 running at 66 Mhz and Chess Genius 2
I have an upgraded Wundermachine running on a PIII at 866 Mhz with Chess Genius 2 and 5
I ran some games for the WM G5(against SSDF engines rated 2395 and 2632) and it appears to play at just about 2600 ..so i was wondering what Chess Chess 2 would be rated at on the faster WM?

IM Thinking it should be ratyed about 2500 but the formulas are coming up higher
i think perhaps the Wiki Estimate of 2350 for CG2 on a 486/66 might be too high to begin with?


Perplexed Regards
Steve

[Steve B]

50*(log(866/66)/log(2)) = +175

60*(log(866/66)/log(2)) = +222


175 ... 222

It could be a bit more I think. From the SSDF list there is for instance Chess Genius 3.0 DOS with a rating of 2256
174 Genius 3.0 486/50-66 MHz 2256 24 -24 866 61% 2175
But the same program on a Pentium 90 MHZ was already
158 Genius 3.0 Pentium 90 MHz 2312 25 -24 824 60% 2240
If you'd speed up that Pentium 90 MHz to 866 MHz and assume an optimistic 70 elo increase per doubling (Rybka claims it gets 70 elo per doubling), I get about 228 elo increase over Pentium 90 MHz.

So assuming a Pentium III 866 MHZ is about a ten times faster Pentium 90. That would be an upper limit, but not so unrealistic; if it was a large program that would not fit in the cache of the 486,- I'm not sure, but I don't think the 486 actually had an on board/chip instruction cache?-, and knowing there are Pentium III 866 procesors with 256 kB L2 cache but there were also for instance the Celerons, that were Pentium IIIs but had IIRC only 128 kb L2 cache (I had one of those, 500 MHz Celeron Pentium III), but otherwise these were identical (Of the 866 Pentium III I think the 128 kB version was not called Celeron anymore). If this chessprogram would now fit completely in that 256 kB cache of a real Pentium III, and for an old program I think it might, then that would be beneficial to its execution speed, irrespective of the increased clock speed to 866 MHz. So with some luck I think you would get more that figure of +222 that you get from just looking at the increased clock speed.

Eelco

Hi Eelco
interesting you should use Chess Genius as an example because it is Chess Genius that i am asking about


Specifically
the Wiki shows an estimated rating for the WunderMachine of 2350..
this was for a WM with a 486 running at 66 Mhz and Chess Genius 2
I have an upgraded Wundermachine running on a PIII at 866 Mhz with Chess Genius 2 and 5
I ran some games for the WM G5(against SSDF engines rated 2395 and 2632) and it appears to play at just about 2600 ..so i was wondering what Chess Chess 2 would be rated at on the faster WM?

IM Thinking it should be rated about 2500 but the formulas are coming up higher
i think perhaps the Wiki Estimate of 2350 for CG2 on a 486/66 might be too high to begin with?


Perplexed Regards
Steve

[bob]

Hi All
If a chess engine is currently rated 2350 running on a 486 at 66 Mhz..
what would the approximate rating increase be if that same exact program runs on a Pentium III at 866 Mhz?
ignore any differences in Ram
a range of 25 Pts would be fine(I.E. an increase of 100-125 for example)
is the increase due entirely to the increased clock speed or do the different processors have any impact on the increase?
(same clock speed but different processors)

Thanks In Advance Regards
Steve

Hard to answer, but the general rule would be about 60-70 Elo each time you double the speed of the program. Clock speeds are not always indicative of program speed, thanks to games Intel has played in the past, however...

so from 66 to 866 is about 3.6 doublings
thats 60*3.6 or an increase of about 210?
Matthias formula seems to indicate about 175
a good range then would be 175-200
that seem accurate?
Thanks
Steve

I think it might be MORE, not less. Because, for example, an OOE (P6, aka pentium-pro and beyond) is far faster than an equivalent 486 at the same clock speed.... A pentium pro will kick a pentium at the same clock speed, and the pentium is far better than an old 486...

[Ajedrecista]

Hello again:

Hello Matthias:

Hello:

50*(log(866/66)/log(2)) = +175

Wow! Really a quick answer. I have done this math and it is around 185.69, so a little more than 175, but with the uncertainties, yes, it could be a good approximation... but I do not understand that formula: why multiplying by 50 and dividing by log(2)?

The idea is that doubling the speed gives +50 Elo increase on same hardware.
The better processor justifies a greater increase, thus +60.

I know that some people would want to assume +70 or even +80 because of the better processor.

So my estimate is quite pessimistic.

Now I understand the formula. Thank you. I think I read a while ago in Rybka Forum that doubling the speed worths between +60 and +70... not sure 100%.

But for my experience I say that clock speed is not all in performance gains: also the microprocessors. Running JetChess 1.0.0.0 (a single core, w32 perft counter) in i5 is between 3 and 10 times faster (depends on the positions, maybe is between 3 and 6 or 3 and 7, I do not remember well) than in D930 in spite of have 205 MHz less.

Regards from Spain.

Ajedrecista.

First of all, I want to correct a typo from my previous post: 2999 - 2793 = 206 (and not 205).

I have reminded an example concerning JetChess that shows the big difference between microprocessors. This test was ran with the same conditions (1 GB hash and single core):

http://talkchess.com/forum/viewtopic.ph ... ht=#421918

In this example, speed grew a factor of ~ 3.57 in spite of 2793 MHz < 2999 MHz. This is why I say that clock speed is important, but not the only thing that gain Elo. As someone replied in other post, cycles are not comparable IMHO.

Regards from Spain.

Ajedrecista.

[rbarreira]

Hi All
If a chess engine is currently rated 2350 running on a 486 at 66 Mhz..
what would the approximate rating increase be if that same exact program runs on a Pentium III at 866 Mhz?
ignore any differences in Ram
a range of 25 Pts would be fine(I.E. an increase of 100-125 for example)
is the increase due entirely to the increased clock speed or do the different processors have any impact on the increase?
(same clock speed but different processors)

Thanks In Advance Regards
Steve

Hard to answer, but the general rule would be about 60-70 Elo each time you double the speed of the program. Clock speeds are not always indicative of program speed, thanks to games Intel has played in the past, however...

What do you mean by games? Maybe it's just me, but you make it sound like it's an illegitimate thing for different CPU architectures to have different IPC (instructions per clock), while in fact it's perfectly normal due to different pipelines, branch prediction, bigger caches etc. But you know all that, which is why I found your statement odd.

[Steve B]

Steve,

Please have a look at this resource:

http://tldp.org/HOWTO/BogoMips/bogo-list.html


For the 486 66MHz I think the speed index is around 33.
For P3 866MHz the speed index is ca. 1730.

These numbers give a much bigger difference that the raw clock speed comparison. Bob is absolutely right - once cycle of the 486 is NOT the same as one cycle of the P3.

I used these index values to calibrate DOS Box version of the Genius 3 program to my dedicated Mephisto unit (there are Motorola 68030 speeds here as well). The results were really close to the index predictions.

Regards,
PK

Hi Pk
Thanks for your post
i missed it earlier and only now saw it

So what is your guess as to the Elo for Lang's Chess Genius 2 running on a PIII(866Mhz)?
after some testing i did it seems Lang's Chess Genius 5 running on this hardware comes in at or near 2600
i guess another way to think about this is..
how much stronger is Chess Genius 5 then Chess Genius 2 running on the same hardware?
Best Regards
Steve

[bob]

Hi All
If a chess engine is currently rated 2350 running on a 486 at 66 Mhz..
what would the approximate rating increase be if that same exact program runs on a Pentium III at 866 Mhz?
ignore any differences in Ram
a range of 25 Pts would be fine(I.E. an increase of 100-125 for example)
is the increase due entirely to the increased clock speed or do the different processors have any impact on the increase?
(same clock speed but different processors)

Thanks In Advance Regards
Steve

Hard to answer, but the general rule would be about 60-70 Elo each time you double the speed of the program. Clock speeds are not always indicative of program speed, thanks to games Intel has played in the past, however...

What do you mean by games? Maybe it's just me, but you make it sound like it's an illegitimate thing for different CPU architectures to have different IPC (instructions per clock), while in fact it's perfectly normal due to different pipelines, branch prediction, bigger caches etc. But you know all that, which is why I found your statement odd.

Do you recall 486. DX2? DX4? PIV with big clock but way slower than slower-clocked CPUS unless you wanted to stream memory and nothing else?

Games, as I said. And meant.

Much saner since the post-PIV days, thank goodness...

BTW the 486 was 1 instruction per clock at best...

[kasinp]

Steve, here are my thoughts:

1) SSDF shows ~ 51 Elo between G2 and G5.

It's easy to arrive at this once you notice that G3 and G4 are the same strength on 486 and P90 (their average ratings are off by 2 Elo). What remains is a direct comparison of G2 to G3-G4 on 486, and a direct comparison of G3-G4 to G5 on P90.

Note that SSDF lists G2 rating on 486 66MHz at 2234 (vs. 2350).
I am quite sure that I once read that SSDF ratings were increased by Wiki by 100 Elo to align them better with USCF. This could explain the bulk of this discrepancy.

2) Starting with 2234 Elo, and assuming 55 Elo per doubling, I would estimate G2 rating on PIII 866 MHz at:

2234 + 55*(LOG(850/33)/LOG(2)) = 2492 Elo (SSDF) or 2592 Elo (USCF).

G5 rating would be 51 Elo higher, as per point 1.
This formula uses a PIII 866MHz speed index for non-Linux systems, and a 486 50-66MHz speed index - both from the link I gave in the earlier post.

Hope this makes sense,
Peter

[Don]

Hi All
If a chess engine is currently rated 2350 running on a 486 at 66 Mhz..
what would the approximate rating increase be if that same exact program runs on a Pentium III at 866 Mhz?
ignore any differences in Ram
a range of 25 Pts would be fine(I.E. an increase of 100-125 for example)
is the increase due entirely to the increased clock speed or do the different processors have any impact on the increase?
(same clock speed but different processors)

Thanks In Advance Regards
Steve

Hard to answer, but the general rule would be about 60-70 Elo each time you double the speed of the program. Clock speeds are not always indicative of program speed, thanks to games Intel has played in the past, however...

Yes, that's hard to answer. The problem is that there is no general rule that applies at all depths. At shallow depths a doubling is worth a whole lot more. On a 486 66 MHZ pentium we are getting a lot more per doubling that a program today would get for a doubling. And I'm sure it has a lot to do with the program. I'm almost positive that modern programs get a lot more ELO increase for doubling that the old program got.

[Laskos]

I'm almost positive that modern programs get a lot more ELO increase for doubling that the old program got.

That would mean that the difference in strength between modern programs and old ones would increase with the time control. I have to check the rating lists (no time now), but I doubt this statement.

Kai