Re: Mersenne: What computer is OK today?
Hi Yuri, At 10:48 PM 11/11/98 -0800, Yuri Sorkin wrote: I participated in GIMPS from the very beginning, Yuri was indeed one of the earliest members, LL testing exponents below 500,000 with a 486. How times have changed! And now I see that my P5-166 (SDRAM, MMX, Intel) doesn't get from Primenet anything for LL-test quite awhile. Since I'm going to buy a new desktop soon and consider its suitability for GIMPS to be a certain indicator of satisfactorily performance, I wonder what computers get exponents for a test now? In version 17, less than a P-75 will get factoring work. Less than a P-133 will get double-checking assignments, P-133 and higher will get first-time LL tests. A year from now, less than a P-200 will get double-checking assignments, P-200 and higher will get first-time LL tests. If your P-166 is getting double-check assignments now, there are three possible causes: 1) Your CPU hours per day is set below 24. A P-166 running 12 hours a day is treated like a P-83. 2) Your machine is substantially slower than other P-166s. Look in local.ini and find the line RollingAverage=xxx. If xxx if a lot less than 1000, then this is the cause. 3) There is a bug in the program. If so, please send your ini files to me by private email. For those on a tight budget, consider building a machine around the Intel Celeron 300A. There have been many success stories overclocking this chip to 450MHz with a 100MHz front-side bus. This suggestion is only for the most knowledgable hardware enthusiasts - see the Usenet newsgroup comp.sys.intel for more information and ideas. Best regards, George
Re: Mersenne: What computer is OK today?
At 10:48 PM 11/11/98 -0800, you wrote: I participated in GIMPS from the very beginning, yet trying to join it with 386-SX. And now I see that my P5-166 (SDRAM, MMX, Intel) doesn't get from Primenet anything for LL-test quite awhile. Since I'm going to buy a new desktop soon and consider its suitability for GIMPS to be a certain indicator of satisfactorily performance, I wonder what computers get exponents for a test now? Four months back? That's weird. My P166's first assignment is an LL test. You did select "24 hours" as the amount of time per day the machine will be up right? -- .*. "Clouds are not spheres, mountains are not cones, coastlines are not -()circles, and bark is not smooth, nor does lightning travel in a `*' straight line."- -- B. Mandelbrot |http://surf.to/pgd.net _ | Paul Derbyshire [EMAIL PROTECTED] Programmer Humanist|ICQ: 10423848|
Re: Mersenne: What computer is OK today?
On Thu, 12 Nov 1998, George Woltman wrote: For those on a tight budget, consider building a machine around the Intel Celeron 300A. There have been many success stories overclocking this chip to 450MHz with a 100MHz front-side bus. This suggestion is only for the most knowledgable hardware enthusiasts - see the Usenet newsgroup comp.sys.intel for more information and ideas. I have a question about the new Celeron chips with the 128K cache. Suppose one were to get an overclockable Celeron 300A and ran it at 450MHz. That would mean you would have 128K of L2 cache running at 450MHz (I might not have some of this right--if so, someone please let me know!). I wonder how it would compare speedwise (running LL tests on an exponent in the 550 to 600 range, say) to a regular PII-450 with 512K L2 cache running at 1/2 the processor speed? The Celeron L2 cache would be quicker, but would that be offset by it's small size (relative to the PII cache) when running LL tests? Has anyone done any systematic testing? I've seen reports of overclocked Celeron 300A chips benchmarking as high as PII-450 chips, but I suspect that LL tests are such that this might not be true for those of us in GIMPS. Kel
