Your config is very stable under 98SE (even ACPI works flawlessly) and has full driver support.
>RAM: Atech 1GB DIMM DDR PC2700 333mhz x 3
but read about what you have to do with big memory. Few solution exist.
And yes, having 3 equal RAM modules are not optimal on Nforce2.
>some DOS ... games
Nforce2 is not optimal chipset for games under pure DOS. There is not support for ISA DMA emulation over PCI.