The NanTan FMA3500 is a intel 80486 based notebook computer released in 1991, and came in several different models with several different versions of the intel 486, and primarily used desktop components. It was sold under various brand names including BSI, Eurocom, and AMS. These days the DX models are listed on auction sites as "486 DX Professional" as that's the actual consistent branding printed on the case above the keyboard.
The FMA3500 came in 3 different models: The base level FMA3500, FMA3500SX, and FMA3500C, and it appears it may have been available in all three currently available screen technologies of the time (STN Monochrome, DTSN Color, and Active Matrix TFT Color). These can be told apart by very distinctly different screen bezels (STN = 9.4" Centered, DTSN = 10.4" centered, Active Matrix = 9.4" offset. Palm wrests, hinges, and batteries can differ a little from one another as well based on these and the occasional variation. One of the most distinctive features is the use of desktop components - making this a "baretop" - aka, other companies could order these empty from NanTan and then populate them with their own 3.5" Hard Drives, SIP Memory, 3.5" Floppy Drives, and Socket 1 compatible 486 CPU and sell it as their own models, though these also were apparently sold direct as "NanTan" products themselves at times as well.
These laptops are kind of amusing to enthusiasts and collectors due to their distinctively "out-dated" appearance, looking more like something that would have been a 386SX or a 286 era machine due to the 8.9LB weight, blocky white chassis, the fact the PS/2 port has a TOGGLE SWITCH to turn it on and off, and the battery in back - one of the most distinctive features - is a 12v NiCAD model held on by thumbscrews.
- Intel 486 DX-33 (FMA3500, FMA3500C), or 486 SX-25 (FMA3500SX) CPU, Socket 1 (Press-fit)
- AWARD BIOS
- 4x SIP Memory Slots for up to 16MB of RAM, 32MB Maximum theoretical
- 1.44MB 3.5" Desktop floppy Drive
- Standard Desktop 3.5" 40 pin IDE HDD up to 528MB in capacity
- WD VGA Graphics Chipset
- STN Monochrome 9.4", DTSN Color 10.4", or Active Matric TFT 9.4" LCD Panel 640x480p only
- internal Speaker Sound
- Mechanical Keyboard
- PS/2 Port, switchable via a toggle switch located on the side by the RS232C Serial Port
- 19V NiCAD Battery that attaches to the back of the computer with Thumbscrews
- some later models came with a Trackball built in where the "486 DX" Logo is located.
Expansion was provided via a "Docking Station" that attached in place of the battery with a pair of thumbscrews. This "Docking Station" of sorts provided 2 ISA expansion slots for adding a network card or a sound card to the machine.