Info PrimeGrid Challenges 2025

[TennesseeTony]

The next round is FACTORIAL sieve, GPU only. 180 seconds for a 75% power limited 4090 (versus 90 seconds on AP27, with FAR more points offered on AP27). 10m10s on a 2080Ti @80% power limit (8m on AP27). Sieve projects IIRC have always offered more points, for the lack of fame (finding a prime). Sadly that does not seem to be the case this time around, but at least we are not talking hours on slower cards.

 

[StefanR5R]

Actually the next one was previously meant to be at a new project (or remake of an old project which was called "Factorial Prime Search". So, not the corresponding sieve project.

Recently, the 2025 Challenge Series table was edited to show "Compositoral" as the 7th challenge project, still at the same time slot of 18-25 September 08:00 UTC (7 days).

In June, PrimeGrid started a new project called Factorial / Compositorial Sieve.

The project is necessary step in preparation for new Factorial Prime Search and Compositorial Prime Search on PrimeGrid.

Now the big question is: Will the September challenge be held at "Factorial/Compositorial Sieve"? I don't think so; why would they list the challenge project as "Compositorial" then? Or will they start a Compositorial Prime Search project in time for the challenge? I haven't seen anything in the message board about it. Perhaps somebody said something at discord (which I don't read).

At the PrimeGrid preferences web page, none of the existing projects is marked as World Bamboo Day Challenge challenge project yet.

 

[Ken g6]

Recently, the 2025 Challenge Series table was edited to show "Compositoral" as the 7th challenge project, still at the same time slot of 18-25 September 08:00 UTC (7 days).

They edited it down to 5 days now.