About 7820X Running SGEMM Blackout

Sean Zhang's Avatar

Sean Zhang

04 Nov, 2017 03:12 PM

When my 7820X is OC to 4.5GHz @ 1.3V (A reasonably safe frequency), it can pass AIDA64 FPU test and other CPU Benchmarks. But when runing GB4, it blackouted at SGEMM. I guess it might be the new AVX512 instruction set for what you haven't optimized yet?

  1. Support Staff 1 Posted by Colin on 06 Nov, 2017 05:53 PM

    Colin's Avatar


    Thanks for reaching out to us about this. Could you let me know what version of Geekbench 4 you're using and what you mean by "blackout"?

    Primate Labs Inc.

  2. 2 Posted by Sean Zhang on 07 Nov, 2017 12:37 PM

    Sean Zhang's Avatar

    Sorry for my confusing "Blackout". It means the computer automatically
    restart before completing the whole test. It was Geekbench 4.1.4. And now
    it seems is OK with Geekbench 4.2.0. But there is another problem. It seems
    unable to get the correct memory bandwidth with a quad-channel CPU. I
    checked some samples like 7900X, 6950X, and my own 7820X.
    the memory copy/bandwidth marks are far too low, approximately a
    dual-channel value. Here is one of my own score:



  3. Support Staff 3 Posted by Colin on 07 Nov, 2017 08:04 PM

    Colin's Avatar

    Hi Sean,

    I see, thanks for clarifying. I will look into the 7820X score and let you know as soon as I can if I'm able to provide some more insight into the issue.

    Primate Labs Inc.

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