From my notes:
*** Orange Micro 386 and 486 NuBus Cards
The Orange386 card was launched in early 1991. The card has a soldered 386SX processor running at 16MHz or 20MHz with a socket for an optional 387 fpu. Four SIMM sockets are provided which must be filled as pairs, using 256KB, 1MB or 4MB SIMMs. The 386SX processor is essentially a 16 bit design which limits RAM expansion to 16MB. For expansion, the card has one 8 bit ISA slot and one 16 bit ISA slot, which take standard PC cards. An optional peripheral kit provides serial, parallel and floppy drive ports via a cable connected to the card.
Other PC functionality is provided by hardware on the host Mac. Built-in graphics is only CGA standard, and is displayed in a Windows on the Mac desktop. Alternatively, an ISA graphics card can be installed for use with a dedicated monitor, but this combination occupies a lot of space inside the Mac. **Detailed information about this card is available online at
http://www.vintagemacworld.com/.
The original 386 card was revised in 1993 and rebranded OrangePC. Three versions were offered initially: basic 386SX, enhanced 386SX and an Intel 486 version. Unfortunately, the press release for the 386 cards does not define "basic" or "enhanced", but I believe that the enhanced version had an ISA slot. In December 1993, Orange Micro announced a fourth version with a Cyrix 486SLC2 processor. These were the last PC compatibility cards that had an ISA slot and which used 30 pin SIMMs.
*** OrangePC NuBus 200 Series
With the NuBus 200 Series, Orange adopted a "pick and mix" approach to features and processor speed. Depending on your budget, you could buy a 486 card with VGA or SVGA graphics, real serial and parallel ports and a PCMCIA expansion connector. The VGA/SVGA chip is provided by Video 7. The PCMCIA connector, which replaced the ISA slot on previous NuBus cards, was intended for a sound or network card, but other devices may work. Orange Micro advised users to use monolithic network drivers, rather than installing Card Bus or PCMCIA management drivers. Almost everyone who managed networked PCs in the early 1990s will agree with this recommendation. The cards have a single 72 pin SIMM slot and the processor can be upgraded. Orange Micro specified 32MB as the largest SIMM but it would be worth trying a 64MB or 128MB SIMM if you have one lying around.
The 210 is the entry level model with limited graphics capability (VGA) but a real serial and parallel port. The 250 has better graphics (SVGA) and a PCMCIA connector, but no serial or parallel ports. The 290 is the top of the range model with all of the functionality provided by cheaper models. A 220 model later appeared with similar functionality to the 210 but with SVGA graphics. Orange Micro's cards were more expensive than an Apple Houdini card of the same period, but had more PC compatibility (eg the ability to support software protection dongles).
The 200 series cannot use a separate monitor and video is displayed in a window on the Macintosh desktop or, for best performance, in full screen mode. A multiscan monitor that supports 640x480 and 800x600 resolution is required.
*** OrangePC NuBus 300 Series
The last NuBus PC compatibility cards were the 300 Series. The only version for which I could find a detailed specification is the OrangePC 340. It uses faster 486 or 5x86 processors, and has two 72 pin SIMM slots (officially, the maximum SIMM size was 32MB). New functionality that would appeal to games players was added. In addition to two serial ports and a parallel port, the cards acquired a SoundBlaster module with separate audio in/out connectors and a games controller port. The PCMCIA option from the 200 series was discontinued.
