[AcceptYourDeath]

I had alot of trouble running The Witcher 2 as steam version. It crashed way to much back to desktop without any error message. It looked random at first but I`ve reached a point very soon were it would crash ALWAYS by changing from gameplay to a cutscene. (when you`ve walked from ship to that little harbor using some sort of butterfly shield)

So I used this "bcdedit /set IncreaseUserVa 3072" command from the Support Page, and for the first time I could watch the full cutscene and the game continued with gameplay afterwards. So I am confident now I`m able to play Witcher 2 without crashing, but this still has to be proven over time.

I`d like to know what exactly this command did to my PC! Is it permanent? Do I have to perform this "change" every time before launching Witcher 2 (it needs a restart at least, looks like a permanent change)?

And I am curious to know if I have limited my overall performance for my PC in some way by applying this command.

[Guy N'wah]

A little background: 32-bit Windows divides its memory in half: 2GB of user space, where your programs run, and 2GB of system space, where the kernel runs and I/O devices live. So any one application (game, Office, whatever) can have up to 2GB of memory.

The command "bcdedit /set IncreaseUserVa 3072" changes that division: it gives 3072MB (3GB) to user space and 1GB to system space. Not all applications can use the extra gigabyte, but some can: applications that are coded "large address aware" (LAA) are the ones that can.

TW2 is definitely LAA and can use more than 2GB if you let it. On some machines, this makes the difference between the game crashing and not crashing; on others, you may get better performance because resources don't have to be evicted from memory and later read back in so often.

Another well-known LAA application is Photoshop CS2. Photoshop users already know about the importance of this setting.

The change is permanent on your computer; you do not need to make it more than once. It changes the boot configuration of Windows so that it is in effect every time you boot.

Not all computers and not all applications play nice with it. If you find your computer has become unstable, or an application has become unstable, you can revoke it with "bcdedit /set IncreaseUserVa 2048".

This is not necessary with 64-bit Windows. On 64-bit Windows, TW2 already gets the full address space (4GB) that a 32-bit application can have.

[AcceptYourDeath]

Thank you so much for this reply!

So I am running a pair of two 2x2GB Corsair 1600Mhz on Windows 7 32bit! The System tab says "4GB installed 3,48GB in use".

Intel 2500k
Asus Z68 Pro
Asus GTX 570 DC II

This sounds like I did my PC some good at least for a gaming rig. I`ll monitor my PCs behavior for a while. Would it help keeping the OS slick, like not installing and using much applications which dig deep into the system (run in background)? Or could potentially every application freak out which has no "LAA" no matter on which "side" it runs.

Would you suggest Win 7 64bit? Afaik 64bit OS still causing alot of trouble in general running stable (drivers in first place).

[Guy N'wah]

AcceptYourDeath said:

Thank you so much for this reply!

So I am running a pair of two 2x2GB Corsair 1600Mhz on Windows 7 32bit! The System tab says "4GB installed 3,48GB in use".

Intel 2500k
Asus Z68 Pro
Asus GTX 570 DC II

This sounds like I did my PC some good at least for a gaming rig. I`ll monitor my PCs behavior for a while. Would it help keeping the OS slick, like not installing and using much applications which dig deep into the system (run in background)? Or could potentially every application freak out which has no "LAA".

Would you suggest Win 7 64bit? Afaik 64bit OS still causes alot of trouble in general running stable (drivers in first place). ›››

Well, everything you let run in background forces context switches and bogarts CPU time, so yes, cutting down what runs in background can make a difference. Many purists go so far as to "clean boot" (turn off everything that isn't Microsoft services) when booting to play demanding games.

Windows 7 x64 is very stable, and drivers are generally available and stable. The only concern is with older hardware that may not have up-to-date drivers. It may be especially painful to get these working on 64-bit.

Since 64-bit gives you 4GB instead of 2 to 3GB for your biggest 32-bit memory hogs, it is well worth considering.

[Vinterberg]

I got a question:

TW1 crashed every 30 mins for me, Oblivion too BTW..
I used the /bcdedit trick, and since then TW1 has never crashed on me - don't know about Oblivion yet
BUT:
I only got 3 GB total memory in my system, so how "healthy" is it to make all 3 GB available for programs, and essentially 0 GB available for the system?
So far I encountered no problems with using my pc at all, but still.. I'm wondering..

[AcceptYourDeath]

Well I guess I don`t have to consider my hardware as old and should give a Win7 64bit OEM a try. Thx again.

And btw I was one of those purists using my old PC.

[Guy N'wah]

Vinterberg said:

I got a question:

TW1 crashed every 30 mins for me, Oblivion too BTW..
I used the /bcdedit trick, and since then TW1 has never crashed on me - don't know about Oblivion yet
BUT:
I only got 3 GB total memory in my system, so how "healthy" is it to make all 3 GB available for programs, and essentially 0 GB available for the system?
So far I encountered no problems with using my pc at all, but still.. I'm wondering.. ›››

Virtual vs. physical memory. The bcdedit (or /3GB on XP) trick gives your program 3GB virtual address space, not 3GB physical memory. Your program, other applications, and the system compete for physical memory: if there's enough to go around, everybody is happy; if not, the system tries to be efficient in giving memory to the process that needs it soonest.

If there's not enough physical memory to go around, Windows plays Robin Hood, stealing pages from fat rich processes and giving them to needy and deserving processes. In so doing, it's careful to steal read-only pages first. Read-only pages can be reread from the file they came from. (Read-write pages that have been dirtied on have to be written to the pagefile before they can be stolen, so Windows steals these only as a last resort. If this starts happening, your computer is in trouble, everything slows to a crawl, and real-time applications like games may crash.)

The point is, you can run a virtual memory load that somewhat exceeds physical memory, without major efficiency issues, especially if you're running only one application plus the stuff Windows does in the background.

[Vinterberg]

Thank you very much for answering me in such depth!!!

[Guy N'wah]

Vinterberg said:

Thank you very much for answering me in such depth!!! ›››

Thank you for asking. There is so much superstition and outright misinformation in circulation about Windows memory management that it's good to have a chance to set at least some of the record straight.