> As I said before, I suspect what's happening is that the adapter > is detecting something that the BIOS is doing while trying to figure > out the capacity of the disk, and "helpfully" setting up an HPA on > the drive (and doing so so aggressively that all but a thousandth of > the capacity of the disk is lost).
It wouldn't be a Host Protected Area (HPA) as that by definition is an area the host (PC) can't access under normal conditions. Each time an the IDE standard was changed to work around a limitation, the standard dictated what to set in the "old" variables which typically were the maximum value possible. So if you plug in a 200 GB disk, a PC with a 504MB limit will see a 504MB disk, a system with a 137GB limit will see a 137GB disk, etc. So the device wouldn't have to do anything special to support an old BIOS. It might, however, have gotten these fixed values wrong. Since modern systems ignore all the obsolete capacity fields if newer ones are present, they wouldn't notice any mistake. But if your system is looking at one of the old capacity fields and seeing the wrong values, perhaps this is why. I imagine a diagnostic program might be able to do some probing for IDE devices and show what values are reported by which fields. These also bypass the BIOS and talk to the hardware directly. I used HWINFO to diagnose an issue on a PC once where a drive wasn't visible, and it turned out the PnP ICU I was using had moved the IDE port to the tertiary spot which the BIOS didn't support. So that one definitely bypasses the BIOS as it could see the drive on the 3rd IDE controller the BIOS didn't know about. > The machine has 40 MiB of RAM installed. I notice that all three > boards show a maximum capacity of 128 MiB of RAM. If I could ever > find compatible RAM, that's a tempting option. Is it 72-pin RAM, in pairs? Most Pentium boards were. Although it's becoming less common, it still comes up pretty regularly on eBay where I am. Curious how you get to 40 MB if it's in pairs though as it's not a power of 2, unless it's 48 MB and the video adapter is stealing 8 MB for itself or something like that. > Unless I buy an entirely new optical drive, that will at least stay > on IDE, as all the SATA optical drives in the house are in use by > other computers. OTOH, the prospect of actually being able to boot > the thing directly from optical is enticing. You can get IDE/SATA converters quite cheaply. I bought a few of these ones as they cost me under $5 each including shipping, and they are bidirectional, allowing IDE drives to plug into SATA controllers, but also allowing (one) SATA drive to plug into an IDE controller: https://www.aliexpress.com/item/4000263683410.html You don't have another old IDE drive larger than 130 MB you could plug in just to rule out the BIOS as the problem? It really sounds to me like the SSD is just reporting the wrong values. Does the manufacturer have any configuration programs you can use? Many drives can have their capacity reprogrammed to work in environments where a specific size is required (e.g. an existing RAID array) so experimenting with that could be an option. Cheers, Adam. _______________________________________________ Freedos-user mailing list Freedos-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-user
