Hello everybody,
I'm trying to figure out how Windows 9x loads its components and drivers into memory.
Experimenting with UMBPCI, I noticed that Windows always takes all the upper memory and it's usually VMM32 that consumes it all.
But if I don't load UMBPCI, VMM32 only takes a few bytes of conventional memory.
Can anybody please explain me what's going on? Is the rest of VMM32 being loaded into extended memory directly?
I'm trying to understand because I thought that those free UMBs could be used by other software/games too, but I suppose they should be used BEFORE Windows boots, is that correct? Is there a way to prevent Windows from taking all the upper memory?
If I restart in DOS mode, I see the free upper memory.
Also, are all the virtual device drivers loaded from the vmm32.vxd and its folder and the iosubsys folder? Are there other important folders? Which VXD files are being loaded in that VMM32 program that's taking the upper memory?
I also would like to know if there are any downsides to loading EMM386 on each boot, since it puts the processor in protected mode and I remember reading somewhere that that could bring problems.
I'm trying to figure out how Windows 9x loads its components and drivers into memory.
Experimenting with UMBPCI, I noticed that Windows always takes all the upper memory and it's usually VMM32 that consumes it all.
But if I don't load UMBPCI, VMM32 only takes a few bytes of conventional memory.
Can anybody please explain me what's going on? Is the rest of VMM32 being loaded into extended memory directly?
I'm trying to understand because I thought that those free UMBs could be used by other software/games too, but I suppose they should be used BEFORE Windows boots, is that correct? Is there a way to prevent Windows from taking all the upper memory?
If I restart in DOS mode, I see the free upper memory.
Also, are all the virtual device drivers loaded from the vmm32.vxd and its folder and the iosubsys folder? Are there other important folders? Which VXD files are being loaded in that VMM32 program that's taking the upper memory?
I also would like to know if there are any downsides to loading EMM386 on each boot, since it puts the processor in protected mode and I remember reading somewhere that that could bring problems.
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