:: How to Setup the 3GB switch ::

[Da_elf]

do you need to use the 3gig switch in vista? whats the ram limit ?

[Candelero]

Under Vista, I doubt you need the 3GB .

Best regards,
nikki Candelero

[RErender]

#1 result in Google for "Vista 3GB switch"....

http://usa.autodesk.com/adsk/servlet...linkID=9242018

[FlytE]

Thanks... my brain wasnt working so i didnt even think to google it (yes it was THAT bad a day).

Anyway I bit the bullet and got the 64 bit version working so im not bothering with the switch now. I didnt have an excuse really - quad core xeon, 16gb ram, fireGL V5600

teehee I love my new puter.

Thanks again.

[victor.nsy]

After last update of the graphic card, 3GB ran fine.

With the 4GB switch, it crashes at 1.5GB Memory used.
With 3GB, we go through 2.3GB...

I Remember quite clearly there isn't a 4GB switch , what were you guys trying to do?

[victor.nsy]

This 3GB switch have nothing to do with Physical RAM. It's for the Address space.
Every process or running application have a dedicated 4GB max virtual address space
on a 32 bit machine. The default is such that 2GB of it goes to the user process and
the other 2GB goes to the Kernel and OS operation. What the 3GB switch does is that it
changes the default to 3GB user process and 1GB System. Especially for 3d artist
drivers and other windows process would be left with 1GB max of virtual address space,
which may cause problem. As far as my research goes it's for 32bit server that manage
ever growing files that may require additional VAS as time progress. Because server
usually do not have great graphics card or multiple devices attached or a user riding
on it, so 1GB for Kernel and OS process is suffice. Many misunderstood the use of this
switch. And moreover some use /PAE switch with the /3GB switch which in windows
environ will make the machine less efficient.

virtual address space does not means physical ram in anyway. Remember also this apply
to 32 bit windows and 32 bit hardware. Once you hit 64bit there is no 4GB VAS limit.
If you wanna know more google at the right spot.

A good understanding of the /3GB switch is essential before using it.

[RErender]

sigh... Either a large scene will crash at 1.8 GB usage or it will render if it stays under 2.8, that is the difference..

[infotech]

In addition to adding the /3GB switch to the boot.ini ... I found that adding the switch "/userva=####" (where #### is memory value falling between 2900 - 3030) overall stabilizes the system.

This adjusts the balance between the user and kernel memory. I typically start out with 3030 and lower it until stable.

Different devices will each claim/reserve a portion of kernel memory ... and at times, the /3GB switch does not leave enough kernel memory for the system ... causing instability under heavy load.

The biggest culprit to this are video cards which are now available with massive vram (1GB +). Installing a GPU with more Video Memory will reduce total available memory even more.


Source -- http://msdn.microsoft.com/en-us/library/ms791558.aspx