Probably this value limits the amount of RAM the system can take (4096 means 3gb physical ram + 1gb for drivers etc)
You can try to increase this value to 8192, but then your probably going to experience the same problems as before.
Arris Windows Server 2008 Enterprise x86 can detect up to 64GB of physical memory.Single application cant use more than 4GB, but the OS itself can use up to 64GB.
The x86 processor hardware is augmented with additional address lines used to select the additional memory, so physical address size is increased from 32 bits to 36 bits. This increases maximum physical memory size from 4 GB to 64 GB. The 32-bit size of virtual address is not changed, so regular application software continues to use instructions with 32-bit addresses and (in a flat memory model) is limited to 4 gigabytes (GB). The operating system uses page tables to map this 4 GB address space onto the 64 GB of total memory, and the map is usually different for each process. In this way the extra memory is useful even though no single regular application can access it all simultaneously.
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