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Old 2002-08-17, 16:03   #12
xtreme2k
 
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http://www.gchoi.com/images/p95.jpg

Is this a bit slow for 1000 iterations on a P4 2.5GHz?
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Old 2002-08-17, 16:38   #13
Tasuke
 
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You are not yet doing the Iteration (LL)portion of the test. You are currently doing the p-1 factoring. Your timings look about right.
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Old 2002-08-17, 17:15   #14
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Yah I know its not LL yet, it just looks a bit slow to me. Going for about 3% per hour...
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Old 2002-08-17, 19:15   #15
bayanne
 
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Nah, it really is doing fine, don't worry. This is BIG crunching on a 33m
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Old 2002-08-18, 00:34   #16
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33252977 took me a little over 67 hours on a P4 1.8 with 448 Mb allocated. That's about 1.5% per hour...

[Tue May 28 14:29:20 2002]
Self-test 1792K passed!
[Fri May 31 09:58:40 2002]
UID: dswanson/pc1800A, M33252977 completed P-1, B1=385000, B2=10395000, E=2, WY1: 5CE27B7D
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Old 2002-08-18, 14:18   #17
vader
 
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Default P4 speed (factoring)

If you have another computer (non-P4) you may want to do your factoring on that one and manually move the exponent to the P4 when it is time for the LL test.

If I remember correctly my Duron 1000 MHz is about twice as fast as my P4 1600 MHz when it comes to factoring (although I think that was regular trial factoring and not P-1). So it seemed like a waste to let the P4 do anything other than LL, and now I do all factoring on the Duron.

I don't think I ever checked how the two processors compared on P-1. Does anyone have any info on that?

(By the way, all this applies to v21.4, I don't know if anything has happened to factoring speed in the more recent versions)
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Old 2002-08-18, 14:27   #18
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Quote:
Originally Posted by dswanson
33252977 took me a little over 67 hours on a P4 1.8 with 448 Mb allocated. That's about 1.5% per hour...

[Tue May 28 14:29:20 2002]
Self-test 1792K passed!
[Fri May 31 09:58:40 2002]
UID: dswanson/pc1800A, M33252977 completed P-1, B1=385000, B2=10395000, E=2, WY1: 5CE27B7D
Thats the COMPLETE factoring right? Not a Stage 2 P-1? mine is only a Stage 2 P-1 and its already taking 3% her hour. Not counting the initial trial factor to 2^68 and Stage 1 P-1 I think mine is way over 4 days.
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Old 2002-08-18, 14:34   #19
bayanne
 
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Default Re: P4 speed (factoring)

Quote:
Originally Posted by vader

(By the way, all this applies to v21.4, I don't know if anything has happened to factoring speed in the more recent versions)
In version 22.7 :

New features in Version 22.7 of prime95.exe

"Trial factoring above 2^64 on a P4 now uses the SSE2 instructions. This is more than four times as fast as the previous version. "

Worth getting the upgrade :D
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Old 2002-08-18, 22:42   #20
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Quote:
Originally Posted by xtreme2k
Thats the COMPLETE factoring right? Not a Stage 2 P-1? mine is only a Stage 2 P-1 and its already taking 3% her hour. Not counting the initial trial factor to 2^68 and Stage 1 P-1 I think mine is way over 4 days.
It's a complete stage 1 + stage 2. I didn't have to factor any deeper because the exponent was assigned to me already factored to sufficient depth, i.e. I was given
Test=33252977,68,0
which is now
Test=33252977,68,1

I don't have the breakdown for hours in stage 1 vs hours in stage 2.

The 67 hours is a bit misleading, since my wife crashed the computer in the middle of the stage 2, so it was down for a few hours before I got home from work to rescue it. :(
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Old 2002-08-19, 00:21   #21
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Quote:
don't think I ever checked how the two processors compared on P-1. Does anyone have any info on that?
P-1 testing uses the SSE2 code, so the P4 will be much faster. Factoring does not use SSE2 code (except in the beta client, and then only over 64 bits) so that is why the Athlon is faster at that..
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Old 2002-08-19, 06:05   #22
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Hey hey!
Kinda offtopic but just wanted to say hello to dswanson. Thanks for dropping in. I am one of those you contend with for small DC's everyday at 0600GMT. It sucks when you beat me to it :) but much better than going to some random fellow who is going to take months
Onwards to proving M38!!
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