hi OP,
Sorry for your troubles :(. Can I ask if you have installed the two required patches for FX series 8 core CPUs in Windows 7x64. These two Microsoft patches change the parking status of the cores and the other patch does something else, i forget.
If you don't know what I"m talking about, then it's a minor oversight on your part as windows 7 was not built to support true 8 cores and will underutilize them by nature. If you need more info about what i'm talking about, i can link you directly to the microsoft download page for these two patches.
Hope this helps your score.
FYI, I have almost the same setup as you. I even had the Trident 2400 kit at one point.
Now, something else i'm going to tell you. If you were using a Phenom x6 in win7, then switched to a FX 8 core, you WILL notice everything a bit less responsive. I'm telling you, these patches ARE REQUIRED in order for windows to better use all cores.
I noticed the same lag from my phenom 1100t --> FX-8150 when I had that. I almost wanted to go back!
I HIGHLY recommend you look into windows 8.1 x64. your motherboard was built to officially support it, so at this point, there really is no excuse. Plus, you don't have to worry about these patches. AMD worked directly with microsoft on this aspect in windows 8 to make sure that at the basic foundation level, 8 cores would be fully utilized efficiently and to max potential in windows.
TL,DR ----- You need patches for windows from Microsoft to use 8 core CPUS, or you need to switch to windows 8.1 x64
-hax0rmort
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