I found that my xeon lowers CPU clock, when using vr4. Xeons AVX offset is locked, you can't avoid that (maybe v3 custom bios can do that, but unsure). So, the question - vr4 uses AVX ?
53Ghz vs 44Ghz for rendering.
VrayBenchmark doesn't low my CPU clocks.
P.S. Arnold behaves the same, was very surprised. Maybe there's smth inside new compilers ?
Also found this:
Haswell was the first "wide" core from Intel (256-bit FP). In order to preserve power, the Power Management Unit (PMU) power gates the upper 128-bit of the FP when 256-bit instructions are not executed. In somewhere between August and September of 2014 Intel changed the behavior of the Turbo on Haswell. Previously the Turbo behavior was identical regardless if the upper 128-bit of the FP was executing or not (i.e same clocks for 128-bit and 256-bit workloads). In the microcode released in September 2014 the Turbo behavior was changed significantly, from static to workload dependant. In this microcode and all the newer ones the Turbo clocks are exactly the same for 128-bit workloads as before, but significantly lower for 256-bit workloads. On my CPU the difference is 400MHz.
53Ghz vs 44Ghz for rendering.
VrayBenchmark doesn't low my CPU clocks.
P.S. Arnold behaves the same, was very surprised. Maybe there's smth inside new compilers ?
Also found this:
Haswell was the first "wide" core from Intel (256-bit FP). In order to preserve power, the Power Management Unit (PMU) power gates the upper 128-bit of the FP when 256-bit instructions are not executed. In somewhere between August and September of 2014 Intel changed the behavior of the Turbo on Haswell. Previously the Turbo behavior was identical regardless if the upper 128-bit of the FP was executing or not (i.e same clocks for 128-bit and 256-bit workloads). In the microcode released in September 2014 the Turbo behavior was changed significantly, from static to workload dependant. In this microcode and all the newer ones the Turbo clocks are exactly the same for 128-bit workloads as before, but significantly lower for 256-bit workloads. On my CPU the difference is 400MHz.
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