[QUOTE=kladner;457309]I just finished the DC of [B][URL="https://www.mersenne.org/report_exponent/default.php?exp_lo=39957347&full=1"]39957347[/URL] [/B]with a match. This is one of the oldest first testsI have seen in a while. It makes me wonder what hardware Dennis Moran was running, and how long it took to complete. (I don't remember right off what system I had in 2007, though certainly it would be AMD and likely single core.) It took my current system about 25 hours, running one worker window with all four cores. It would be a real commitment taking that on with that era's CPUs, and a real accomplishment in system stability terms.

There is a sense of connection through running LL on the same exponent almost ten years apart, and getting the same result, that makes me happy.
Verified 2007-10-29 Dennis Moran E42BD92AD22BF139
Verified 2017-04-23 ktony E42BD92AD22BF139[/QUOTE]

[QUOTE=GP2;457314]The double-checking wavefront is now passing through exponents that were first-time tested in October 2007, so these are the oldest unverified exponents, except for the stragglers [M]41979059[/M] and [M]41979199[/M] from earlier that same year. All older exponents and all undated exponents have already been double-checked by now.

So in that sense, [M]39957347[/M] wasn't an outlier for 2007, rather it would have been a typical first-time test of that era.[/QUOTE]

Yeah looks pretty typical to me. Here's my most recent batch of four DCs: [M]39743941[/M] [M]39748277[/M] [M]39748339[/M] [M]39749153[/M]

It may have been more noticeable as I probably slipped a category or two in the recent past. I had been seeing 40M assignments, with more like 2009 dates. I hadn't paid attention, and likely had not realized the change until I recovered stability and standing.

[QUOTE=kladner;457309]I just finished the DC of [B][URL="https://www.mersenne.org/report_exponent/default.php?exp_lo=39957347&full=1"]39957347[/URL] [/B]with a match. This is one of the oldest first testsI have seen in a while. It makes me wonder what hardware Dennis Moran was running, and how long it took to complete.[...][/QUOTE]
As others have said, this was indeed typical for first-time tests in 2007. That's when I joined GIMPS, and after a couple of double checks in the 19M range I was assigned [URL="https://www.mersenne.org/report_exponent/?exp_lo=39788533&exp_hi=&full=1&ecmhist=1"]M39788533[/URL] in September of that year. It took six months for my Athlon to complete it (working about 6-8 hours per day). The test was finally confirmed by a double-check three months ago.

Now, how about this? I am still using that same old Athlon to this day! It is still going strong and to my knowledge has never produced a bad result, taking about 5-6 months for the current double-checking work on 42-45M exponents.

[QUOTE=Brian-E;457609]Now, how about this? I am still using that same old Athlon to this day! It is still going strong and to my knowledge has never produced a bad result, taking about 5-6 months for the current double-checking work on 42-45M exponents.[/QUOTE]

But 5 to 6 months of electricity for a single exponent is pretty expensive...

If you are using that Athlon solely to run Prime95, then let's assume the computer uses 100 W for 6 months, that's approximately 430 kW-h in total. The cost of electricity in the Netherlands was about € 0.18 / kW-h as of 2015, so that means it costs almost € 80 per exponent in electricity costs, for exponents in the double-checking range. I don't know, maybe there's four cores, so divide the cost by four, it's still € 20 per exponent.

There are cheaper alternatives. For instance, using the cloud with Amazon AWS c4.large instances, it takes 130 to 150 hours to text exponents from 42M to 45M, at a cost of about $0.0115 per hour, or $1.50 to $1.75 per exponent.

Using an old computer for Prime95 is like driving an old gas guzzler automobile, it's not very cost effective or environmentally friendly.

@GP2 The computer is switched off when I'm not using it. Running mprime is not its primary function.:smile:

Not sure if this is for the happy me, or unhappy me, threads, hehe...

Already did 4% LL work on [URL="https://www.mersenne.org/report_exponent/?exp_lo=332264497&full=1"]this baby[/URL] (ETA August 2017) when P-1 to some extended limits (running in parallel) found that big factor. Happy to have a factor and avoid a lot of work. Unhappy that I didn't take George's money this time neither... :razz: Well, actually EFF's money... Maybe next time...

A personal milestone- my bike odometer turned over 24,000 miles on the way home from work the other night. (But took the picture below because I wasn't sure how picturesque the background would be at exactly 24,000. Should have scouted it out in advance).

Norm

[QUOTE=Spherical Cow;458351]A personal milestone- my bike odometer turned over 24,000 miles on the way home from work the other night. (But took the picture below because I wasn't sure how picturesque the background would be at exactly 24,000. Should have scouted it out in advance).

Norm[/QUOTE]

Congrats

Less than 1,000 more gets you around the entire planet.

[QUOTE=Spherical Cow;458351]A personal milestone- my bike odometer turned over 24,000 miles on the way home from work the other night. (But took the picture below because I wasn't sure how picturesque the background would be at exactly 24,000. Should have scouted it out in advance).

Norm[/QUOTE]
Where did you get that bike light? A friend gave me a similar one but never told me where I could get them.

[QUOTE=henryzz;458362]Where did you get that bike light? A friend gave me a similar one but never told me where I could get them.[/QUOTE]

I got it locally (Tucson) at a bike store, and believe the brand name is Bright Eyes- I see them on Amazon, and on the Bright Eyes website. Its been a good light, and has lasted many years. Probably will need to replace the rechargeable battery in the next year or so.

[URL="https://www.brighteyesproducts.com/"]https://www.brighteyesproducts.com/[/URL]

Norm

[QUOTE=petrw1;458360]Congrats

Less than 1,000 more gets you around the entire planet.[/QUOTE]

That's right- my next milestone. Once around the planet! Though I'm sure I won't be attempting a second lap.

Norm