32bit game 64 bit system

Aerorush

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Can a 32bit game (Microsoft Flight Simulator X) utilize more than 4GB on a Windows Ultimate 64bit system?
I have read many posts on the 32bit/64bit issue, including one on this page, but the question still remains, will a user with Vista Ultimate 64bit see any improvement in gameplay by adding RAM to a system with 4GB already installed?
 
Solution
Regarding how much memory a 32 bit app can use in a 64 bit OS, the answer is "It Depends".

32 bit Windows defaults to 2GB for application usage, and 2GB for the system. Many/most 32 bit apps are coded with this limit in mind, and even in the case where there is more system memory available they may not use more than 2GB. However, *IF* the application is coded and flagged as LARGE_ADDRESS_AWARE, then there is the potential to use up to 4GB, which is the limit for a 32 bit process. So the short answer is "No, there isn't a way to make a 32 bit app use more than 4GB of address space/memory for itself."

However....


Please keep in mind that even if the game is the only thing that YOU may be doing at the moment, your...
Regarding how much memory a 32 bit app can use in a 64 bit OS, the answer is "It Depends".

32 bit Windows defaults to 2GB for application usage, and 2GB for the system. Many/most 32 bit apps are coded with this limit in mind, and even in the case where there is more system memory available they may not use more than 2GB. However, *IF* the application is coded and flagged as LARGE_ADDRESS_AWARE, then there is the potential to use up to 4GB, which is the limit for a 32 bit process. So the short answer is "No, there isn't a way to make a 32 bit app use more than 4GB of address space/memory for itself."

However....


Please keep in mind that even if the game is the only thing that YOU may be doing at the moment, your computer has a lot more in it's plate. So in the case where the OS can handle the added address space, there is a benefit to adding more RAM than an individual process can use because then that process will have access to it's limit, rather than potentially having to page data in/out of active memory.

Keep in mind, as well, that once you are exploring the limits of (32 bit) address space, you may well receive more benefit from a faster Hard Drive (raid... SSD...) than from more RAM - Simply because the principal bottleneck in a desktop environment is storage, not memory.
 
Solution

Aerorush

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Hello Scott,

Thanks for your educated and comprehensive reply.
I've taken a Dell XPX720 DuoCore 2.67GHz system that originally had WinXP, 4GB RAM and a 320GBHD and upgraded it to a 600GB HD, Vista Ultimate 64bit and the nVidia 9800GTX+ 512MB.

I wanted to add more RAM, but although the MB has 8 slots, Dell says the MB can only use 4GB max. Pity.

So at this point, I think I've realized all the performance I can out of this system.

I used nVidia's nTune OC utility and squeezed another 14% out, but it was unstable so I went back to factory defaults.

Thanks again.

Philip
-Aerorush.com