- Joined
- Dec 27, 2008
A lot of you may know this already but I discovered this morning that OCCT does engage the CPU's AVX instruction set. I'm not talking about the Linpack tab with AVX option checked, I'm talking about the main OCCT tab.
I emailed OCCT with this question a couple of weeks ago but haven't heard back from them. So I was experimenting with the AVX Ratio Offset in my bios for the first time and had HWMonitor open at the same time. I could see that although the CPU core ratio was set to 48x when I ran the OCCT CPU stress test it dropped back to 46x, just like it does when I run Prime95. What I don't know is if OCCT is using the AVX 1 or the AVX 2 instruction set. I tried to register for their forum so as to be able to ask some questions like this but it has been "down for maintenance" for a long time and is probably innactive.
On the other hand, the XTU stress test does not seem to engage the AVX instruction set as it does not cause the CPU ratio to drop. I mention that because I have read where people said that XTU uses the same stress test method that Prime95 does. Well, if that's true it must be a pre AVX Prime95 version that is being referenced.
A three hour OCCT stress test has become my go to OC stability test. It requires less voltage to pass than the newer Prime95 versions (and generates lower temps) but gives adequate assurance that I am stable in the range of applications I use. I cannot say that for XTU which even if I can pass it when run overnight still leaves me with random blue screens and lockups.
I emailed OCCT with this question a couple of weeks ago but haven't heard back from them. So I was experimenting with the AVX Ratio Offset in my bios for the first time and had HWMonitor open at the same time. I could see that although the CPU core ratio was set to 48x when I ran the OCCT CPU stress test it dropped back to 46x, just like it does when I run Prime95. What I don't know is if OCCT is using the AVX 1 or the AVX 2 instruction set. I tried to register for their forum so as to be able to ask some questions like this but it has been "down for maintenance" for a long time and is probably innactive.
On the other hand, the XTU stress test does not seem to engage the AVX instruction set as it does not cause the CPU ratio to drop. I mention that because I have read where people said that XTU uses the same stress test method that Prime95 does. Well, if that's true it must be a pre AVX Prime95 version that is being referenced.
A three hour OCCT stress test has become my go to OC stability test. It requires less voltage to pass than the newer Prime95 versions (and generates lower temps) but gives adequate assurance that I am stable in the range of applications I use. I cannot say that for XTU which even if I can pass it when run overnight still leaves me with random blue screens and lockups.
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