I7-3770k higher IBT Performance with HyperThreading Off

[ShuttleLuv]

Okay I'll buy that. Given the limited sample size, it had only one likely cause in my head

Just re tested. Setting the threads to "auto" from "all", available memory to max or near, all above mentioned settings, HT performance is within a point if not even with HT off when enabled (4c/8t).

 

[SonDa5]

Note how sonda is testing only 1024 mb of memory per test. I started out with the following:


Sandy 2600K clocked at 4.5 ghz HT ON / AVX enabled / Windows 7 SP1 / IBT 2.54

Sandy 2600K clocked at 4.5 ghz HT OFF / AVX enabled / Windows 7 SP1 / IBT 2.54

Initial test was done much like sonda, with 1024 mb available mem tested.Now note, I have 12 gigs of DDR3 im running here. First results put HT on about 10-11 points gflops behind HT disabled. Cache thrash the guy above would say. However I dug alittle deeper and started fiddling with the available memory to test. Each increase in available memory to test the gflops rise. Eventually, testing all available memory or close to it puts the performance back up even give or take a point or two with HT disabled. So if the available memory is changing this, it is most certainly not a cache thrash issue and more a implementation of AVX / memory output issue.

I am going to try it with a higher memory size and post results when
I get time. Thanks. I only have 8GB of DDR3.

 

[ShuttleLuv]

I am going to try it with a higher memory size and post results when
I get time. Thanks. I only have 8GB of DDR3.

Cool I will too when I get the chance.