Working AST Research Premium II 386SX/20 desktop. Tested. It POSTs, keeps time, and boots MS-DOS 6.22 from the original hard drive with no floppy in the drive.
This is the 1990 Premium II SX, not the later DX/25 or DX/33. The 20 MHz 386SX and 16 KB cache are on AST’s plug-in CPU/memory module. Onboard Super VGA, IDE, and floppy controller, two serial ports, parallel port, and a bus mouse port. ISA slots are open for a sound card. About 128 KB of the 4 MB is reserved for system and VGA BIOS shadowing. No math coprocessor. The 387SX socket is empty and CMOS is set with the coprocessor disabled, which is required on these boards.
The CMOS battery has been replaced and the clock holds. The IDE cable has been replaced. The original Maxtor 7131AT, about 125 MB, made in Singapore in July 1993, is installed as the only hard drive. It was partitioned, formatted with FORMAT C: /S, and boots clean DOS 6.22.
Tested: power-on, POST, CMOS holds time after the new battery, onboard VGA outputs a picture, hard drive boots to a C: prompt, floppy drive reads.
Specs:
- CPU: Intel 80386SX at 20 MHz, 16 KB cache on the CPU module
- RAM: 4 MB
- FPU: none
- Video: onboard SVGA
- Hard drive: original Maxtor 7131AT, about 125 MB, booting DOS 6.22
- IDE cable: new
- CMOS battery: new
- Floppy: [3.5 in, 5.25 in] Both tested and working
- Cards installed:
- Case: original AST, very minor scratches and stains, bezel has mild yellowing
Included: computer, power cord, new IDE cable. Not included: monitor, keyboard, mouse, DOS disks, sound card.
Ships from Las Vegas. The desktop is heavy, so shipping is calculated. Local pickup is fine. No returns on a tested vintage PC.
