@vampirepills Just to be sure, you're lifting the CPU core limit after the game loads, right? Trying to run Sims 3 on one CPU core will tank performance on any system.
If that's not the issue, is OneDrive running on your computer? The easy way to tell is to look for a cloud icon in the lower-right corner of the screen; if you see it, right-click it and pause syncing, then try again to play.
NRaas mods should be fine, but please list the ones you're using, for reference. And as a side note, the only two that are core mods are ErrorTrap and UntranslatedKey; the rest are script mods. There are only about six core mods in popular use; the vast majority of the mods out there are script mods, with some tuning mods available as well.