I’ve noticed many people complaining about the OS Memory Pool LOW issue on the steam forums and no one really helping them resolve it. So, I found a great tutorial and decided to list it here for everyone. Check it out:

Open the registry editor. That’s done by going to Run, then type in “regedit.”

In the registry:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management

Double click on “PagedPoolSize”. Hexadecimal is listed first. Change the “Value Data” to one of these below:
Note: You only need to enter EITHER Hexadecimal or Decimal. They both are the same.

Code:
Megabytes Hexadecimal Decimal
192Mb 0c000000 201326592
256Mb 10000000 268435456
384Mb 18000000 402653184

You do not need anything bigger than 400Mb… in most cases 300Mb is too much as well. The bigger the number, the more memory you devote to the Paged Pool.

Once you are done, make sure you reboot your computer.