Intel Announces New Prime95 Suckage in Skylake

[Gödel]

..

Intel Skylake bug causes PCs to freeze during complex workloads

(Sorry, couldn't resist the wording variant of the "Seasonic Announce New Prime Series PSU's" thread.

 

[Mercutio]

Now we just have to hope that all our Skylake CPUs aren't destined to turn up as paving materials likth FDIV-bug impacted P54C Pentiums were.

 

[Handruin]

They claim a BIOS fix can solve this. I'll be interested in what followup tests show.

 

[Chewy509]

I'm actually a little surprised that Intel don't test internally with Prime95 or a similar application?

 

[Buck]

I'm actually a little surprised that Intel don't test internally with Prime95 or a similar application?

I was thinking the same thing. Then I wondered, am I reading the situation correctly? Maybe I am wrong, but it seems that not every Prime95 instance produces the same results with Skylake. So, could Prime95 be running on a Skylake CPU for 24 hours, and the problem is never encountered?

 

[Gödel]

FWIW:.

How to test your PC for the Skylake bug

 

[ddrueding]

Interesting. I wonder if this explains some of my issues with doing an overclock; I use Prime95 and was having inconsistent results. Looking forward to trying again after the fix.

 

[DrunkenBastard]

Interesting. I wonder if this explains some of my issues with doing an overclock; I use Prime95 and was having inconsistent results. Looking forward to trying again after the fix.

My understanding is that you need to be careful of what version of Prime95 you are running. Newer versions will push AVX instructions in the fpu in a way that really diverges from actual real world scenarios. IIRC version 27 or something like that is best to avoid AVX. If you are using an AVX version make sure you have adaptive/offset vcore turned off.

 

[sdbardwick]

My understanding is that you need to be careful of what version of Prime95 you are running. Newer versions will push AVX instructions in the fpu in a way that really diverges from actual real world scenarios. IIRC version 27 or something like that is best to avoid AVX. If you are using an AVX version make sure you have adaptive/offset vcore turned off.

Horseshit.
AVX and AVX2 (FMA) instructions are used by Prime95 exactly as they are designed to be used. Idiots who didn't/don't understand the response of the CPU to AVX instructions spread misinformation - usually like "Prime95 caused my overclocked and overvolted CPU to die!" because the additional (and documented) voltage rise triggered by AVX instructions destabilized their CPU.

 

[sdbardwick]

Newer versions will push AVX instructions in the fpu in a way that really diverges from actual real world scenarios. [Emphasis added]

Absolutely not divergent from real world situations, unless you consider FFTs a non-real world scenario.