Please visit donation page to help the project cover running costs for this month

Toggle Menu

Join PrimeGrid

Returning Participants


Leader Boards



1) Message boards : Number crunching : 2 tasks of 10 cores running simulantiously (Message 150386)
Posted 3 days ago by Profile GrebulonerProject donor
Actually, to be the bearer of bad news, if you're talking about the Ryzen 2700 on your account, you only have 8 physical cores. The other 8 threads are logical. There are many threads on this forum about this discrepancy and how to get the most out of such a system. Search for "hyperthreading".

Regardless of that, to address the matter at hand, I don't think it is actually doing both at the same time, but rather switching between the two units. This happens a lot when you have mixed long (e.g. Woodall) and short (e.g. PPS) tasks. When you get near the end of a task, Boinc downloads a new one, but when they are vastly different sizes, it starts to switch back and forth because of a) different deadline setups and b) weird logic, until the first finally finishes.

Or, I could be off base. Can you take a screenshot of your Boinc window showing both tasks?
2) Message boards : Number crunching : Tesla anyone? (Message 150137)
Posted 27 days ago by Profile GrebulonerProject donor
Thank you Scott for the reply. I find that V100 is about as fast as 2080 ti, but much slower than 3080 or 3090.
Any ideas when the 40 series may come out, since the 3080 and 3090 are priced so ridiculously high?

Late next year is the expected time based on their history of releases. As to cost, that really depends on what AMD and Intel do in the meantime, where the world is in pandemic recovery (and tariffs for Americans), as well as the cryptocurrency market, which is the cause of the current card cost inflation.
3) Message boards : Wieferich and Wall-Sun-Sun Prime Search : PRPnet near finds to PG account? (Message 149887)
Posted 38 days ago by Profile GrebulonerProject donor
As far as I have heard, all the near-Wieferich and near-WSS that were found on PRPNet were correct (that was probably already known), and also no near-Wieferich or near-WSS were missed!

They can still be seen at:

Of course this is not an answer to your question.


Indeed, that is good news. And it's a little amazing to me to see the 3 computers I had my near finds on 7 years ago and realize that they are still in service!

The erroneous find is because I had a computation whoopsie with my GPU that reported an actual Wieferich prime (A=0) in error, which was quickly caught, but the find is still listed as a +1 on my PRPnet stats page :).
4) Message boards : Wieferich and Wall-Sun-Sun Prime Search : PRPnet near finds to PG account? (Message 149878)
Posted 39 days ago by Profile GrebulonerProject donor
Is it possible for those of us that ran WFS/WSS on PRPnet those many years ago and had near finds to get those results added to our PG accounts like is done with the other PRPnet project primes?

(Of course, the erroneous WFS find which is somehow still listed on my PRPnet account should not transfer...)
5) Message boards : General discussion : Top Computers (Message 149585)
Posted 55 days ago by Profile GrebulonerProject donor
For me, I would use the information to inform a next purchase. I am focused on SOB tasks. So I know that I want something with 2 AVX-512 units, and a cache big enough to fit them, but I don't really know where the sweet spot is between cost and performance. From the list you linked, I see that some i9-9900k's are at the top. What I don't know (or maybe just don't understand) is if these i9's are scoring so well due to large LLR performance like I'd want for a SOB machine, or if they are great at cranking out PPS or GFN or AP work units. Based on my, admittedly limited, understanding the characteristics for each type of work differs.

If I'm failing to understand and the stats I'm looking for are available, I'd very much appreciate learning.


Whetstone is just bulk floating point, it really isn't taking AVX/2/512 into consideration. My 8 yo i5 3570 and top of the (Intel) line i9 10980XE are within a couple hundred points of each other in the Boinc benchmarks.

Many of us on these forums run a wide variety of hardware at varying levels of extremeness and can tell you the stats you're after or give you recommendations based on what you want and your budget. Based on what you say above, this is my two cents without knowing what your budget really is:

If you're looking for 2 AVX-512 units, you're already looking at a very limited list of CPUs: Used Skylake-X (7000X/9000X) or new Cascade Lake-X (10000X) CPUs. There are also Skylake-SP/Cascade Lake-SP/Ice Lake-SP (coming soon) 6000+ series Xeons, but those are super expensive for lower relative performance. My 10980XE is close to fitting 2 SOB's in its cache, but not quite, and I get better efficiency by running 2x9 threads. Cache requirement is only going to increase, so lower core counts will be more limiting in that area, but they can be found for much less.

I should also say that HEDT and "bang for buck" are not two things that really go hand in hand. You can get used 7980XE/9980XE CPUs for a little less than a new 10980XE (think $700-800), and you'll find the maximum cache, there. BUT, the boards are expensive. You will need to buy a big, expensive and high quality cooler (skip air, go straight to the biggest AIO liquid cooler you can get or fit), because these chips will use a ton of power, especially once you find out how low the default AVX-512 clocks are and decide to overclock them to something more reasonable. Of course, all Intel and AMD CPUs will use a ton of power if you want to let them run at their top stock clocks (new 11900k will pull 300W without overclocking, Threadrippers can do 500-1000W easy). In a modern CPU, performance potential at stock is directly correlated with the cooling capacity of the system.

For comparison, I run my 10980XE at 3.5-3.8GHz AVX-512 speeds (stock 2.7), depending on project. It uses 350+W at those speeds, and with the best 420mm liquid cooler making moderate noise, sits in the mid 80s Celsius. I could easily add more speed to that if I wanted to put up with the noise or go custom liquid cooling.

I hope I'm not scaring you off, just want you to be aware of what you're getting into, especially with cooling.
6) Message boards : Number crunching : Badges III (Message 149382)
Posted 63 days ago by Profile GrebulonerProject donor
7) Message boards : Number crunching : Tour de Primes 2021 (Message 148371)
Posted 98 days ago by Profile GrebulonerProject donor

Yay! On the board!
8) Message boards : Number crunching : i9-10900K or Xeon W-1290P? (Message 148364)
Posted 99 days ago by Profile GrebulonerProject donor
Bur, what are the brand and model(s) of the systems you are considering? Depending on what they're putting inside, there are factors that could make one system more powerful than the other, particularly in the case of the cooling system or space for a bigger cooling system to be installed, but also overclocking might be supported on the i9 system depending on what their motherboard choices are.

With modern CPUs, the true determiner of system performance has become how well the chip can be cooled. The more powerful the cooler, the higher the turbo bins used by the chip.
9) Message boards : Number crunching : Good Riddance 2020! Challenge (Message 147543)
Posted 121 days ago by Profile GrebulonerProject donor
Well, I've learned one important lesson from this challenge:

You can't run PG on an overclocked (350W!) 10980XE, 3930k, E3v3 Xeon, their respective high powered GPUs, and a laptop, plus pfsense router, storage server, all the networking gear for the house, 4 stereos (for surround sound!), and the bedrooms' lights off of one 20A, 120V circuit. (No, they were not all in one room.)


I have a very old house where the wiring was updated to good, modern stuff in the 90s, but not, apparently, to the (then) standard of one circuit breaker per room.

The straw that broke the camel's back? I turned on the little monitor I use for direct access to the server.

There has been a relocation of hardware. >.<
10) Message boards : Number crunching : Good Riddance 2020! Challenge (Message 147508)
Posted 123 days ago by Profile GrebulonerProject donor
Shiny new hardware is always nice to have :)

Current PPS-DIV FFT size is 480K

Oh, indeed it is!

Just under 4MB per task then, excellent, thank you.

Next 10 posts
[Return to PrimeGrid main page]
Copyright © 2005 - 2021 Rytis Slatkevičius (contact) and PrimeGrid community. Server load 4.58, 4.08, 3.70
Generated 15 May 2021 | 18:57:10 UTC