
Процесс короче пошёл.
Дальше восстановить работоспособность Promise DC4030VL-1. Также проверить пойдёт ли прошивка более поздняя от LCS-6941 с поддержкой LBA.
Дальше тесты, эксперименты... продолжение следует

Как на счёт xt-ide universal bios?
Здесь если можно по подробнее
Но у Promise DC4030VL-1 вроде как PDC20130, так что xt-ide universal bios тут бесполезен (да и в целом у него другие задачи - обеспечивать поддержку IDE устройств и CF в том числе на более древних компах (XT-AT-386...)IDE controllers on VLB and PCI bus
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VLB and PCI IDE controllers are more complex since they have an actual controller between bus and IDE drive. This controller can buffer the data so the CPU can read 32-bits at a time. Early VLB controllers are limited to PIO-2 but later VLB controllers and (all?) PCI controllers also support PIO modes 3 and 4. These later VLB multi I/O cards have two IDE connectors so you should use one of those even if you don't need the other IDE connector.
Unfortunately many of the controllers work only at PIO-0 by default. Some VLB multi I/O cards have jumpers to set transfer rates but most require controller specific programming to enable higher PIO modes. It is possible that your VLB multi I/O card don't offer any advantages over ISA multi I/O cards if your BIOS does not support the IDE controller on the VLB card. There are DOS drivers for many VLB IDE controllers so BIOS support isn't a necessity.
At the moment XTIDE Universal BIOS has native support for QDI Vision QD6500 and QD6580 VLB IDE controllers. There is also very experimental support for the Promise PDC 20230-C and 20630 VLB IDE controllers. The support is included in MODULE_ADVANCED_ATA that is included in official 386 builds by default.