Don't anyone throw a brick at me, but I'm willing to bet it is your video card drivers.
With your system you should not have to tweak anything. You might have trouble recording video in LOD 1 while moving.... but you can adjust anything as much as you'd want with hardly a whine out of your machine. See my specs below to compare.
I might also suggest modifying your virtual memory settings manually instead of allowing windows to set it. I only have 2GB of installed physical memory, so I set my Page File Space up to allocate 9GB of room on my hard-drive to be set aside. I think it is in Control Panel, Performance Information and Tools, Advanced Tools, Adjust the appearance and performance of Windows, Advanced Tab, and under Virtual Memory press the "Change" button. In the next window that pops up make sure "Automatically manage paging file sizes for all drives" is NOT selected. Then hit the "Custom" check box and enter numbers for an initial size (I said 4GB) and maximum size (I said 9GB) and press "Set". System managed size and No Paging File should not be selected.
Even though windows recommends only 3GB of space I am currently using 6GB. Windows will use space on your hard drive as if it were RAM. A Solid State drive will NOT appreciate you doing this, they are not the same as memory chips, so the risk is yours.
Then update your video drivers, just because.
CPU: AMD FX-8350 8 core processor 4GHz / GPU: GeForce GT 730 @ 1920x1080, 60Hz with 1GB adapter RAM / RAM: Patriot Signature 4GB 1600MHz 240-Pin DDR3 (only 2GB work, don't buy it) / Motherboard: MSI 970 Gaming MS-7693