Hello everyone, I would like to understand with your help if I need, as I believe, to install the Lo-tech 1MB Ram card on my old ps/2 8530 (8086/Nec v30) to be able to increase ram and use the Upper memory part with the program umb!umbs.
Analyzing the memory with various diagnostic utilities I thought to have available the memory between D000 and F000, but the program Test!umbs does not find available memory and running in autoexec the program use!umb (1.9) the PC crashes.
The motherboard has 2 simm 30 pins of 256 kb (512) but the ram available to the system is 640, so I think that another 128 kb are on a chip installed on the mobo, in addition to the 64 kb of the bios and those of the video card.
Does anyone have any advice to give me? Is it possible to load with an XT the command.com in this upper memory area ?
Thank you!