This doesn't always happen, however, which means you sometimes play games on integrated graphics instead of your dedicated graphics card. Some PCs (mostly laptops) will use the Intel chipset most of the time to save power, then switch to the Nvidia GPU when you launch a game. I also see in your dxdiag that you have both a dedicated Nvidia graphics card and an integrated Intel chipset.
That way you know which mod is causing the issue. If you have more than one mod, you can start reactivating them to see if the issue returns. Do you get the issue only when wearing a mod outfit, or on all armor? In any case, try temporarily disabling mods to see if the issue goes away.