feipoa wrote on 2024-01-15, 12:50:

I haven't been following this thread and didn't even know about it until now. So it sounds like mkarcher's BIOS fix would allow, for example, that w95 partition of mine to be 64 GB (in the above example), with the drawback being that the w95 read speeds would be reduced?

It would be nice if we had XT-IDE ROMs for SCSI VLB/EISA controllers.

Windows 9x has its own driver that has no problems with the 8 GB limit.
So mkarcher's BIOS patch will not influence transfer speed.

And his patch works on the EISA 2740 controller series too.

If you use Windows 95 B or C, I'd recommend to have DOS partitions within 1021 cylinders, and to have the LBA partitions to start at cylinder 1022.

DOS partition
NT partition
Extended: 2 GB FAT 16 partition
Cylinder 1022: W95 partition (60 GB?)

Disruptor wrote on 2024-01-15, 12:55:

Windows 9x has its own driver that has no problems with the 8 GB limit. So mkarcher's BIOS patch will not influence transfer spe […]
Show full quote

feipoa wrote on 2024-01-15, 12:50:

I haven't been following this thread and didn't even know about it until now. So it sounds like mkarcher's BIOS fix would allow, for example, that w95 partition of mine to be 64 GB (in the above example), with the drawback being that the w95 read speeds would be reduced?

It would be nice if we had XT-IDE ROMs for SCSI VLB/EISA controllers.

Windows 9x has its own driver that has no problems with the 8 GB limit.
So mkarcher's BIOS patch will not influence transfer speed.

And his patch works on the EISA 2740 controller series too.

If you use Windows 95 B or C, I'd recommend to have DOS partitions within 1021 cylinders, and to have the LBA partitions to start at cylinder 1022.

DOS partition
NT partition
Extended: 2 GB FAT 16 partition
Cylinder 1022: W95 partition (60 GB?)

OK, but I haven't had any problems with it the way it is. I've been running it like this for about 8 years.

feipoa wrote on 2024-01-15, 12:50:

with the drawback being that the w95 read speeds would be reduced?

I don't know why w95 is not enabling fast SCSI in my case and is in yours, but it's not the fault of the BIOS upgrade. I was stuck at 5MB/sec before I changed the ROM too

I'll have to do a binary compare on the miniport drivers included with B and C to see if something changed

As best I can tell there is a bug/drawback in the windows 95 miniport driver (ARROW.MPD) that does not enable FastSCSI on the EISA based 274x controllers. I have confirmed that the driver and associated INF information (stored in SCSI.INF) are 100% binary match between win95 B and C, and feipoa has confirmed FastSCSI works with the VLB version of the card. So the problem must be specific to the EISA adapter.

Does Win98SE exhibit the same symptoms?

feipoa wrote on 2024-01-21, 23:44:

Does Win98SE exhibit the same symptoms?

Yes

Wondering aloud if anyone tested the latest version of this code (2.0) and the driver on an Adaptec AHA-2842A. The last few pages of the thread called out some bugs and instability but it wasn't entirely clear to me what was and wasn't working.

I'm proactively necroposting this as I'm about to go down the path of trying it myself, and perhaps someone here can save me some time with a view on if it works or not.

Either way I'll circle back to this thread with my results, using the version 2.0 code that was posted to Github.

I don't own a VLB card so I can't help you but I've tested the firmware and modified driver on two different EISA systems with two cards and both performed perfectly

Awesome thanks! I'll report back with feedback after I try it. This is a bit further down my list after I get the 486 stable at 160MHz.

maxtherabbit wrote on 2026-07-06, 23:17:

I don't own a VLB card so I can't help you but I've tested the firmware and modified driver on two different EISA systems with two cards and both performed perfectly

Can you tell me more about it? I'd like to test your driver on my EISA 2740W and to look at the changes.
I've reportet about wide (non-fast) performance under Windows9x.
Win95 Performance of 2740W / 2742W
Please remember mkarcher's BIOS patch for enabling disks > 8 GB on that controllers (247X and 284X).

Disruptor wrote on 2026-08-06, 09:54:

Can you tell me more about it? I'd like to test your driver on my EISA 2740W and to look at the changes. I've reportet about wid […]
Show full quote

maxtherabbit wrote on 2026-07-06, 23:17:

I don't own a VLB card so I can't help you but I've tested the firmware and modified driver on two different EISA systems with two cards and both performed perfectly

Can you tell me more about it? I'd like to test your driver on my EISA 2740W and to look at the changes.
I've reportet about wide (non-fast) performance under Windows9x.
Win95 Performance of 2740W / 2742W
Please remember mkarcher's BIOS patch for enabling disks > 8 GB on that controllers (247X and 284X).

Huh? I got the copy of ASPI7DOS from you 🤣

Ah, so it's the BIOS and the ASPI7DOS driver and you also have no solution for Windows 9x?

I want to say the built in 9x driver could handle the larger disks already but I honestly don't remember clearly now