minimum cpu cores?

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dschief
Posts: 163
Joined: Tue Dec 04, 2007 5:56 am
Hardware configuration: Gigabyte Z790 UD AC , i7-14700K (x2) Win11
ASUS Z97_K , i5-4460 (x2) Win10 & UBUNTU 24.04
GPU's ASUS RTX1660 x2, RTX3050 x2
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minimum cpu cores?

Post by dschief »

First day back, after being idle for several years. the first box got up & running no problem, both boxes have same GPU
GTX 760 both downloaded gpu wu's & are running fine . first box has an i7 14700 K & it's crunching along.
the second box has an i5-4460. and is not getting anything to run. Is it a case of just no wu's for that weak a cpu and should I just kill it & run only
the GPU
muziqaz
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Re: minimum cpu cores?

Post by muziqaz »

3 threads or more
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dschief
Posts: 163
Joined: Tue Dec 04, 2007 5:56 am
Hardware configuration: Gigabyte Z790 UD AC , i7-14700K (x2) Win11
ASUS Z97_K , i5-4460 (x2) Win10 & UBUNTU 24.04
GPU's ASUS RTX1660 x2, RTX3050 x2
EVGA1060
Location: California Wine country

Re: minimum cpu cores?

Post by dschief »

the i5-4460 has 4 cores, 1 is driving the gpu, web page lists 3 cpu , so the cores are there. the question is are there any wu's
small enough to run on it ?
muziqaz
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Re: minimum cpu cores?

Post by muziqaz »

There should be. There might be shortage of WUs for such small core count from time to time, though
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Hopbackguy
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Re: minimum cpu cores?

Post by Hopbackguy »

I've noticed a similar phenomenon. I've recently had to replace my iMac as the old one failed. For years I'd been running FAH on a previous release successfully. That was a ten year old Intel based iMac and I was able to specify between 1 and 4 of the 4 cores to be used and usually got work units. I've installed V8.4.9 now on the new one, which is 8-core Apple silicon. I specified to use 2 cpus originally but it never downloaded any WUs. Then I upped to 3 cpus and instantly got a work unit and have kept getting them. A couple of days ago I tried 2 cpus again and got a WU but when that had finished - nothing again until I raised to 3 cpus again. The old setup didnt seem to demand as much computing power.
arisu
Posts: 438
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Re: minimum cpu cores?

Post by arisu »

Hopbackguy wrote: Fri May 09, 2025 9:20 am I've noticed a similar phenomenon. I've recently had to replace my iMac as the old one failed. For years I'd been running FAH on a previous release successfully. That was a ten year old Intel based iMac and I was able to specify between 1 and 4 of the 4 cores to be used and usually got work units. I've installed V8.4.9 now on the new one, which is 8-core Apple silicon. I specified to use 2 cpus originally but it never downloaded any WUs. Then I upped to 3 cpus and instantly got a work unit and have kept getting them. A couple of days ago I tried 2 cpus again and got a WU but when that had finished - nothing again until I raised to 3 cpus again. The old setup didnt seem to demand as much computing power.
That's because the limit is currently (temporarily?) 3 threads so it makes sense that you won't get anything with 2 threads.
Hopbackguy
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Re: minimum cpu cores?

Post by Hopbackguy »

arisu wrote: Fri May 09, 2025 12:00 pm
That's because the limit is currently (temporarily?) 3 threads so it makes sense that you won't get anything with 2 threads.
Thanks, I wondered about that. Has there been an explanation on here do you know about why the 3 thread limit?
muziqaz
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Re: minimum cpu cores?

Post by muziqaz »

There is a bug with fahclient that it sometimes downloads (and fails) WUs on CPU:1 slider.
People seem to be confused about what GPUs require from CPU, and they tend to set the slider to 1 or 2 CPUs next to their GPUs, thinking that GPU requires that slider to be set to 1 or 2 threads. In this set up client would download and immediately fail a WU in some rare cases.
The slider should be set to 0 if user wants to just fold on a GPU.
I have not been able to reproduce this issue myself.
While CPU:1 setting will remain disabled, the next CPU project will have CPU:2 setting back. So people will be able to pick some work on 2 core CPUs
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