Which version for P-III's?

[Uncwilly]

I would keep v23, most bang out of an old machine. You can do good with it low level factoring (less than 64 bits).
My suggestion:
Set it for "What ever type makes the most sense" for the work preference.
Log into the v5 server. Go to "My Account" -> "CPUs".
Select "v4_computers". Set the "Work Preference" to a factoring type assignment (like LMH).
Set your work preference for other CPU's from the website, or client.

[mdettweiler]

Originally Posted by mdettweiler

Why don't you try plopping a copy of v25.7 into a separate folder and selecting "just stress testing" when you start it up, then running a benchmark on both v23 and v25.7? Then, if the v25.7 benchmark is better than that for v23, go ahead and upgrade the v23 installation to v25.7.

Also, I just had a thought: possibly v23 is faster than v24.14 due to something with a misdetected SSE2 setting of some sort? Maybe there's some sort of manual override in prime.ini that would help? (Presumably, if that turns out to be a fix for v24.14, it should work for v25.7, too.)

Ah, never mind about this--I just read the v25.7 whatsnew.txt file and found that apparently it's official that on Pentium, PII and PIII CPU's 24.x and newer are slower than 23.x. In that case, I concur with Uncwilly--you should probably stick with v23. (Though if you have the time, a benchmark comparison with v25.7 definitely won't hurt.)

[xilman]

Originally Posted by davieddy

1947 I think you mean.

Quite possibly.


Paul

[davieddy]

Originally Posted by xilman

I'm still running a PPro. It's a fan heater which does computation in its spare time.

Second or third frost of the autumn here in Cambridge. The computers are keeping my study reasonably warm but I'm going to have to power up some more, or turn on the (gas-fired) central heating, before much longer.


Paul

I use ordinary light bulbs for the same reason.
Snow this morning in Milton Keynes!

David

[petrw1]

Originally Posted by richs

Well, I know there weren't many P-III's contributing to the project before the server migration, but if anyone upgrades to v25.7 on a P-III, would they please let us know how it affects performance? Perhaps this is a question that George will address.... I'm trying to figure out whether to stay put with the v23 version that is faster or to upgrade.

I can't speak for performance since I joined in the v24 days. HOWEVER, one nice surprise I had when I upgraded my PIII (866) was the message along the lines of "You machine is too slow for trial factoring". I was converted automatically to "Trail factoring to low limits". Now instead of it taking 10 days to factor one exponent to 69 bits it will instead take less than 1 day to factor to 64 or 65 bits.

[xilman]

Originally Posted by davieddy

I use ordinary light bulbs for the same reason.
Snow this morning in Milton Keynes!

David

Apparently, it's the first time snow has stayed on the ground in southern England in October since 1934!

Paul

[markr]

Originally Posted by petrw1

Now instead of it taking 10 days to factor one exponent to 69 bits [...]

Up to when it died this year, I used a P166 as firewall/spaceheater. It took 35 days to TF to 68 bits... when TF moved into 69 bits territory I changed it to LMH-type low factoring. V5 server-allocated low factoring would have been ideal, but was not an option at the time.

[davieddy]

Originally Posted by xilman

Apparently, it's the first time snow has stayed on the ground in southern England in October since 1934!

Paul

I recall a May in the 1980s when villages in Eastern England
including Kent were cut off for weeks by copious snow.

[Uncwilly]

Originally Posted by davieddy

I recall a May in the 1980s when villages in Eastern England including Kent were cut off for weeks by copious snow.

You limeys are just whining. Near me one highway closes down for snow in Nov or Dec usually and doesn't open till March usually.

[garo]

Righto! The limeys are totally useless when it comes to coping with snow. Having lived in Massachusetts and northern Italy I was shocked when half an inch of snow once effectively closed Heathrow for a day and a half. We had a metre of snow in 24 hours in Italy and my flight from Milan - even though it was delayed by 5 hours - still took off the next day.

[TheOutcaste]

Thought I'd post my benchmarks for V 23.8, 24.14, and 25.8 from two different PIII systems, a PIII 700 overclocked to 785 MHz, and a PIII 500.

Seems to me that sticking with V 23.8 would be more productive, at least for LL tests. Will have to run some more tests to compare factoring speeds, as V 23.8 doesn't include trial factoring in it's benchmark.

For LL tests:
V 23.8 is significantly faster on both systems
V 25.8 is slightly faster than 24.14
For Trial Factoring:
V 24.14 and V 25.8 are very close with 24.14 having a slight edge, except for 62 bit and 64 bit, where V 25.8 is approx 1.8 times as fast at 62 bit, and 2.2 times at 64 bit.
Anybody know if this is a real difference, or just due to a different number being used in the benchmark?

Intel Pentium III or Pentium III Xeon processor
CPU features: RDTSC, CMOV, PREFETCH, MMX, SSE
L1 cache size: 16 KB
L2 cache size: 512 KB
L1 cache line size: 32 bytes
L2 cache line size: 32 bytes
TLBS: 64
RdtscTiming=1
Prime95 version 23.8    Prime95 32-bit version 24.14    Prime95 32-bit version 25.8
CPU speed: 497.88 MHz   CPU speed: 497.84 MHz           CPU speed: 497.84 MHz, 2 cores
 384K FFT: 140.205 ms.    
 448K FFT: 165.715 ms.    
 512K FFT: 184.326 ms.     512K FFT:  233.152 ms.            
 640K FFT: 250.723 ms.     640K FFT:  329.114 ms.            
 768K FFT: 297.563 ms.     768K FFT:  405.953 ms.            768K FFT:  404.805 ms.
 896K FFT: 356.686 ms.     896K FFT:  484.765 ms.            896K FFT:  485.521 ms.
1024K FFT: 397.246 ms.    1024K FFT:  545.725 ms.           1024K FFT:  545.428 ms.
1280K FFT: 515.379 ms.    1280K FFT:  688.039 ms.           1280K FFT:  686.813 ms.
1536K FFT: 621.652 ms.    1536K FFT:  839.930 ms.           1536K FFT:  837.282 ms.
1792K FFT: 745.158 ms.    1792K FFT: 1013.196 ms.           1792K FFT: 1010.255 ms.
2048K FFT: 821.435 ms.    2048K FFT: 1139.053 ms.           2048K FFT: 1134.834 ms.
                          2560K FFT: 1568.413 ms.           2560K FFT: 1563.621 ms.
                          3072K FFT: 1928.861 ms.           3072K FFT: 1922.032 ms.
                          3584K FFT: 2296.835 ms.           3584K FFT: 2285.068 ms.
                          4096K FFT: 2574.921 ms.           4096K FFT: 2571.534 ms.
                          58 bit TF:  28.246 ms.            58 bit TF:  29.060 ms.
                          59 bit TF:  28.263 ms.            59 bit TF:  29.018 ms.
                          60 bit TF:  28.305 ms.            60 bit TF:  29.216 ms.
                          61 bit TF:  28.281 ms.            61 bit TF:  29.069 ms.
                          62 bit TF:  53.224 ms.            62 bit TF:  28.995 ms.
                          63 bit TF:  53.275 ms.            63 bit TF:  52.493 ms.
                          64 bit TF: 119.297 ms.            64 bit TF:  52.560 ms.
                          65 bit TF: 121.046 ms.            65 bit TF: 120.101 ms.
                          66 bit TF: 123.223 ms.            66 bit TF: 121.847 ms.
                          67 bit TF: 123.508 ms.            67 bit TF: 123.767 ms.

Intel(R) Pentium(R) III processor
CPU features: RDTSC, CMOV, PREFETCH, MMX, SSE
L1 cache size: 16 KB
L2 cache size: 256 KB
L1 cache line size: 32 bytes
L2 cache line size: 32 bytes
TLBS: 64
RdtscTiming=1
Prime95 version 23.8    Prime95 32-bit version 24.14    Prime95 32-bit version 25.8
CPU speed: 785.20 MHz   CPU speed: 785.66 MHz           CPU speed: 785.10 MHz
 384K FFT: 110.267 ms.    
 448K FFT: 130.652 ms.    
 512K FFT: 147.734 ms.     512K FFT:  139.285 ms.            
 640K FFT: 197.615 ms.     640K FFT:  193.755 ms.            
 768K FFT: 233.797 ms.     768K FFT:  242.919 ms.            768K FFT:  239.502 ms.
 896K FFT: 283.061 ms.     896K FFT:  292.917 ms.            896K FFT:  298.295 ms.
1024K FFT: 314.944 ms.    1024K FFT:  334.252 ms.           1024K FFT:  337.509 ms.
1280K FFT: 421.668 ms.    1280K FFT:  444.769 ms.           1280K FFT:  440.820 ms.
1536K FFT: 501.988 ms.    1536K FFT:  533.992 ms.           1536K FFT:  536.297 ms.
1792K FFT: 620.473 ms.    1792K FFT:  642.537 ms.           1792K FFT:  643.779 ms.
2048K FFT: 692.094 ms.    2048K FFT:  714.334 ms.           2048K FFT:  711.348 ms.
                          2560K FFT:  950.812 ms.           2560K FFT:  960.670 ms.
                          3072K FFT: 1176.654 ms.           3072K FFT: 1174.291 ms.
                          3584K FFT: 1412.467 ms.           3584K FFT: 1430.823 ms.
                          4096K FFT: 1643.509 ms.           4096K FFT: 1609.154 ms.
                          58 bit TF: 19.505 ms.             58 bit TF: 20.929 ms.
                          59 bit TF: 20.424 ms.             59 bit TF: 20.570 ms.
                          60 bit TF: 19.937 ms.             60 bit TF: 20.890 ms.
                          61 bit TF: 20.221 ms.             61 bit TF: 20.680 ms.
                          62 bit TF: 38.258 ms.             62 bit TF: 20.862 ms.
                          63 bit TF: 37.546 ms.             63 bit TF: 37.835 ms.
                          64 bit TF: 84.093 ms.             64 bit TF: 37.918 ms.
                          65 bit TF: 86.145 ms.             65 bit TF: 84.570 ms.
                          66 bit TF: 86.262 ms.             66 bit TF: 86.299 ms.
                          67 bit TF: 86.579 ms.             67 bit TF: 87.507 ms.

HTH

Jerry