PrimeGrid's 2023 Challenge Series


[H]ard|DCOTM x5
Jun 22, 2009
The PrimeGrid Challenge Series is an annual competition based on the results of monthly challenges. The purpose of the Challenge is to spotlight a specific project within PrimeGrid's family of projects as well as to offer a little "healthy" competition for PrimeGrid's participants. It is also an opportunity for people to learn more about each specific project and have fun doing it. Below is a tentative schedule for 2023.

2008 Final Standings | 2009 Final Standings | 2010 Final Standings | 2011 Final Standings | 2012 Final Standings | 2013 Final Standings | 2014 Final Standings | 2015 Final Standings | 2016 Final Standings | 2017 Final Standings | 2018 Final Standings | 2019 Final Standings | 2020 Final Standings | 2021 Final Standings | 2022 Final Standings

2023 Challenge Series
DateTime UTCProject(s)ChallengeDurationResults
22-25 January​
A Prime Chinese New Year Challenge3 daysIndividuals | Teams
8-9 March​
15:00:00SGSInternational Women's Day Challenge1 dayIndividuals | Teams
16-23 April​
16:00:00PSPGotthold Eisenstein's Birthday Challenge7 daysIndividuals | Teams
19-24 June​
20:00:00321Blaise Pascal's Birthday Challenge5 daysIndividuals | Teams
8-15 July​
21:00:00CW-SieveMath 2.0 Day Challenge7 daysIndividuals | Teams
15-18 August​
02:00:00AP-27Chant at the Moon Day Challenge3 daysIndividuals | Teams
13-23 September​
11:00:00SoBWorld Peace Day Challenge10 daysIndividuals | Teams
31 October - 5 November​
13:00:00ESPChristmas Challenge5 daysIndividuals | Teams
10-20 December​
Chris Caldwell Honorary Challenge10 daysIndividuals | Teams
The first event in the annual PrimeGrid Challenge series is about to kick off so I figured I would post a thread to get this going and to alert anyone that may not be aware and who may want to participate.

I was thinking I would try to run every event in the series this year so I can get a personal best result for "individual score".
A number of people who were running this last year have indicated they may not be doing so this year so we are probably not going to really be chasing much of a team score but who knows!

The first event kicks off in about 18 hours time from now so I am starting to get this up and running on my rigs:
Welcome to A Prime Chinese New Year Challenge

The first challenge of the 2023 Series will be a 3-day challenge on the PPS-MEGA and GFN-17 MEGA applications, beginning 22 January 12:00 UTC and ending 25 January 12:00 UTC.

Project thread:

If you want to run this new years challenge then you will want to select one or both of the following projects as desired:
Proth Mega Prime Search LLR (MEGA) (CPU only and supposedly multi threading of work units is recommended. I am running this with multit threading set to 4 to test)

AND / OR :
Generalized Fermat Prime Search n=17 Mega (GFN-17-Mega) ( This can be run with both CPU and GPU but I have selected only GPU to run for this and will run Proth Mega on my CPU's)
This is just a short 3 day contest to start the challenge series. Word of warning is that primegrid is about the only boinc project that bunkering is not supported for the contests. Basically only tasks that are downloaded after the contest start will be included in the points for the project. IE: don't load up a bunch of work now but you can run it with 0 cache to test it and then when the contest starts make sure to get fresh work at that time.
I'll be tossing a few cores at these challenges but not like last year. That was my year to run the numbers personally. Looks like I'd have to rent servers to break the top 5. No doping here. All natural.
Yeah I am not renting anything myself. Ended up running the GPU tasks 2 up and trying the CPU tasks 2 threads. Seems a bit faster

I am in the top 10 (barely) this morning but I there always seems to be people that come up from behind so we will see how that holds...
I'm only going to run the PPS Mega on a few CPU cores. Good luck!
Still holding steady in the top 10 after the first day and have actually managed to move up to 8th spot overall.

Wareyore and Skylaar are 66 and 81 respectively:


As a team we are also hanging in the top 10 so far
I don't know how much help it will be but I will have a few systems doing some Mega (cpu) work units. Don't even know if they will complete in time. Most of them had to finish up other work as well....
Down to the last 12 hours of the comp.
I have been bumped down 2 spots and am sitting at 10th place
Wareyore is sitting at 63rd
Skylaar is 79th
Gilthanis is 370th

Overall as a team we are sitting at 10th place after being passed by EVGA.
Looks pretty likely i will get bumped out of 10th. Another user blasting up the ranks on rented computers....
I found a "Titan Prime" during the competition!

Dear Primefinder,Congratulations! Our records indicate that a computer registered by you has found a unique prime number. This computer is running BOINC, is attached to the PrimeGrid project, and is assigned to the Generalized Fermat Prime Search n=17 Mega (GFN-17-Mega). What makes this prime unique is that it's large enough to enter the Top 5000 List in Chris Caldwell's The Largest Known Primes Database.Since you have auto-reporting selected, the following prime was submitted on your behalf:Added 134888 : 135623220^131072+1 (1065922 digits)

That also earned me my first "megaprime" badge
Yeah...I overlooked it as well. This is one of them I would have tried running a bunch of due to a low level badge...hehe.
The team finished 16th on this one. Too many of us forgot it was coming up...haha.
Just over 2 hours till the start of the
Gotthold Eisenstein's Birthday Challenge

The third challenge of the 2023 Series will be a 7-day challenge celebrating the 200th birthday of German number theorist Ferdinand Gotthold Max Eisenstein. The challenge will be offered on the PSP-LLR application, beginning 16 April 16:00 UTC and ending 23 April 16:00 UTC.

To participate in the challenge:
  • Wait until the challenge timeframe starts (or set your BOINC Client download schedule accordingly), as tasks issued before the challenge will not count.
  • In your PrimeGrid preferences section, select only the Prime Sierpinski Problem (LLR) project.
These tasks.... seem to take forever... I have been trying them in a few different ways over the last day or so. They definitely want to run multi threaded but they are taking so long I am not sure what the best number of threads to run is...
for example running 12 threads on my 5900x it was still about 18 hours complete a task... I am going to start the challenge trying these as 24 and 32 threads per depending on the rig in the hopes they will run faster (maybe they will fit in cache better?) seems trying to test this one 2 days out was not enough time...
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so after reading a bit more and talking with MN Scout the "issue" here seems to be these need ~24MB of cache per task and it bogs down if you run more tasks than your cache can accomodate. So 3900x / 3950x / 5900x etc mostly have 32mb l3 cache which is a bit short to run 2 tasks consecutive
My CPU is an AMD 1950X. It is an old Zen 1 sixteen core cpu with 32 threads. The math ability much less than Zen 2.

I'm running BOINC at 50%. PrimeGrid is set to use 8 threads per task. I did this on their website. So 2 tasks running.

I tested by running the one or two tasks for 5 minutes and seeing what the expected time settled to. I'd then set PG to no new tasks, then abort the two. Then make changes, then get two new tasks and see what the new time is.

I settled on using Pavel's AffinityWatcher program to help get a 2nd task going at the same time, and seeing very little impact on the 1st tasks time.

With two tasks, I'm getting an estimate of 1 day 9 hours. With only 1 task at 8 threads I was seeing 1 day 7 hours. Running AW as: AffinityWatcher.exe 4 16 2. Every other thread is loaded to 100 in TaskManager now.

Running like this will let me still be able to use the computer for other tasks. Those 16 threads can do other things. As you can see Chrome, Lightroom, etc are using a further 10 to 25%.
I may be able to squeak in 10 tasks over the 7 day challenge; I for sure will get 8 thanks to the above config.
Small update with 4 days 13 hours to go.
I found that almost all of my computers seemed to choke running 2 tasks at once with the exception of my 5950x which ran a bit faster with 2 tasks at once.
I started running this in eco mode but there is a lot of performance that gets left on the table with these tasks vs a lot of other BOINC projects I run so I turned off eco mode and even setup PBO on my 2 5000 series AMD chips.

Last I checked I am in 26th place with 1 461 343.90 points
followed by MNScout at 179th with 110 154.19 points
round the field is Coleslaw in 250th with 944.57 points

Team is sitting at 17th overall.

Had a few crashes as some of these rigs still get funky with their memory from time to time.
Challenge just finished up.
I managed to hold on to 27th which puts me at 20th overall so far this year for the series
MNScout finished 181 and Coleslaw at 203
Team ended up in 17th for this event.
57 days till the next challenge so I am switching over to start bunkering candidates for the Pent.