Prime95 - 4 instances for Quad Core? + How to use for me?

[Max Dread]

Hi all

I'm running some testing on my PC. I have read in several places that it is best to run four instances of Prime95 if you have a Quad Core. However, I am wondering if this advice is a thing of the past and whether the current P95 automatically tests all 4 cores in a single instance of the app. Could anyone confirm?

Also, while I'm here... I am not an overclocker. I just want to make sure that my almost-silent PC is stable, solid and not too hot. So I was planning on just running it overnight. Would that be enough?

Also, it seems to me that there are benefits to all three of the different tests (Small FFT, Large FFT, Blend) so I thought I could run each one over different nights separately. I can then observes temps, and if all stays under my maximum (and there are no errors reported) move on. Does that sound like a plan?

Cheers

Max

[quest_for_silence]

Could anyone confirm?

Yes, you can set how many threads inside Prime, nowadays (what about downloading it from mersenne.org and check directly?).

Would that be enough?

Providing you're not undervolting, just run Prime for an amount of time comparable to the longest session you can have at PC.

Does that sound like a plan?

Providing you're not undervolting, no, your plan doesn't sound, you don't need to check stability: just check the max heat (give a try also to SmallFFT, sometimes it heats up more the CPU), and you've done.

[Max Dread]

Ciao Luca (that is also my nephew's name)

Many thanks for the quick response.

I have already downloaded it and I ran it for an hour this morning. It did seem to run all four cores so I did not think there was a problem. It was just after reading lots of forums about it that I wondered whether running several instances of the app would somehow be different. Then I realised that most of these forum threads were quite old and I wondered whether P95 had been updated to allow for multi-core CPUs. So it seems the answer is yes and my set up is just fine.

No - I'm not undervolting. Aside from customising the cooling in my case, and perhaps tweaking the volt and latency of the RAM (I THINK - it was so long ago it is tough to remember), everything is unaltered. So basically, I do not need to test for stability. Just for heat issues. Is it not possible for a system to become unstable just because of hardware issues, the age of the hardware, etc. - even when no OC has been done?

Thanks again

Max (Massimo)

[quest_for_silence]

Hi Max (an italian expatriate?)

Is it not possible for a system to become unstable just because of hardware issues, the age of the hardware, etc. - even when no OC has been done?

As Shakespeare said, on Earth everything is possible, depending of the hardware (for instance, a cheap mobo with all electrolytic caps can worn out much quicker than an higher end one with all solid-polymer caps, as well as one equipped with just 3 or 4 phases unheatsinked VRMs over another sporting 8-12 phases heatsinked VRMs): but usually instability problems are more likely related to the software environment, mainly the operating system so that, if you are experiencing such an issue, IMHO the best way is to set up a fresh OS installation on a spare disk/SSD and then check the stability (both of the mobo with a Prime95 blend session, and of the RAM with memtest86 but this latter don't require an OS) off it, without messing with any already installed softwares and peripherals. Also instabilities may be due to a near-to-fail PSU, so take this latter possibility into account, in case.