We wont be able to affect any behavior changes in the app once we investigate this, we would simply mark the app as being able to do this. And if the app was then run on an OS with this tweak, the app would take advantage of it.What happens between the driver/card and the OS, thats well out of our control.

Right, but its only the aperture that is mapped at any one time. So this doesnt have such a large impact on the virtual address space.

Ahh, I see, I think...I read your detailed explanation follow-up on your blog. Thank you again. But I'm still confused by the fact that the 32-bit OS's only see 3GB max to begin with. So for me for example, with 4GB of RAM, the 32bit OS only reports the first 3GB, but if the proper 4TB (I think) switch is implemened, the full second half (2 to 4GB) can be presented to the App and video RAM regrardless of what the OS reports? Or would only the 3rd GB (2 to 3GB) have any play here? Do you see where my confusion lies? Performing the tweak step by step is straight forward, completely understanding it does take some thought.Also, is it becuase FS is only one huge process that it never seems to use swap and we run into this app-space limit in the first place? In other words, swap seems to help when many applications or processes are running simultaniously but it doesn't seem to help FS much if a lot of physical RAM is in the PC. So in theory, wouldn't making parts of FS into seperate processes also aleveate this type of limit?

So your saying that an AGP's video card memory & aperture isn't both mapped at the same time? Just one or other is sounds like your saying. As example my AGP video card has 256mb w/ an aperture of 256mb. I was under the assumption that that both are mapped in this case mapping 512mb of the mem area between 3-4gb.As mentioned in a recent 'Ask Dan's Data' that I posted about over in the hardware forum."If I had a video card with 512Mb or 768Mb of memory on it, it'd take up even more space in the 3Gb-to-4Gb memory map.And if I were still using an AGP graphics card, there'd be another block of memory reserved for the AGP aperture, used when devices on other buses in the computer want to talk to a graphics card on the AGP bus. I've got a PCIe graphics card, though, which sits on the same bus as all of the other stuff and so doesn't need an aperture."http://www.dansdata.com/askdan00015.htm

We are getting off topic, this was about using the /3G switch and the June DX redist, not about details on how AGP operates. I'd have to go back and double-check AGP.