Tseng Labs

Tseng Laboratories, Inc.

Company type	Private
Industry	Computer hardware, Semiconductors
Founded	1983
Founder	Jack Hsiao Nan Tseng
Defunct	1998
Fate	Engineering personnel and graphics technology assets acquired by ATI; merged with Cell Pathways
Headquarters	Newtown , United States
Products	Graphics chips and controllers (e.g. ET3000, ET4000, ET6000, VIPeR)

Tseng Laboratories, Inc.—also referred to as Tseng Labs or TLI—was a producer of graphics chips and controllers designed for IBM PC compatibles. The company was headquartered in Newtown, Pennsylvania, and was established by Jack Hsiao Nan Tseng.

1983–1995

Established in 1983, Tseng Labs initially offered a product that enabled IBM PCs to operate the CP/M Operating System. Following the cancellation of an OEM agreement, TLI introduced Ultrapak, a versatile graphics enhancement designed for IBM PC and XT-compatible machines, which incorporated features typically found in the IBM AT. Ultrapak combined compatibility with both the IBM Monochrome Display Adapter (MDA) and Hercules Graphics Card (HGC) standards and added proprietary 132-column text modes, carving out a specialized position in business environments for mainframe terminal emulation. The UltraPAK Short variant served as the foundation for DFI's MG-150, which became one of the most popular MDA/HGC compatible graphics cards.

Tseng Labs pushed beyond standard IBM specifications with offerings such as the ColorPAK in 1985—a CGA-compatible card supporting 400-line graphics—and the EVA and EVA/480 series launched in 1986. These products extended the IBM register set to provide a resolution of 640x480—offering 130 more lines than EGA—and introduced hardware acceleration for windowing, panning, and zooming functions.

Moving away from retail graphics boards toward supplying OEM chips, Tseng’s VGA controllers were incorporated into computers produced by leading manufacturers including Compaq, Dell, IBM, NEC, STB Systems, and Diamond Multimedia.

Between 1990 and 1995, during the Windows 3.x period, Tseng's premier VGA-compatible chips—the ET3000, Tseng Labs ET4000, and ET6000—held a dominant position. The ET4000 series stood out for its rapid ISA bus interface despite relying on conventional DRAM for frame buffering.

Tseng Labs introduced several pioneering technologies that have since become standard in graphics hardware: expanded register sets; support for packed pixel formats including 8-bit, 15/16-bit high color, and 24-bit true color modes; early adoption of local bus graphics architectures; integrated local bus controllers; and Image Memory Access (IMA), which allowed high-speed asynchronous video input directly into frame buffers.

Building on IMA technology, Tseng developed VIPeR video image processing chips capable of delivering superior live and computer-generated video quality. VIPeR found adoption among premium video solution providers such as Matrox and Jazz Multimedia. While other manufacturers embedded basic algorithms within their graphics controllers, Tseng maintained a unique strategy by developing dedicated video processing chips in subsequent product generations.

1995–1998

During the mid-1990s market consolidation in graphics cards, Tseng suffered significant declines in market share, falling behind rivals like S3 Graphics and ATI Technologies. A critical disadvantage was Tseng’s late incorporation of a RAMDAC into their product line, only achieved with the ET6000 chip, which weakened their competitive standing during the later years of the ET4000’s lifecycle.

Faced with difficulties securing memory supplies and lacking sufficient capital to develop an advanced integrated 3D engine (the ET6300), Tseng’s board decided to halt next-generation product development to preserve financial resources while exploring acquisition options. This culminated in ATI acquiring Tseng’s engineering personnel and graphics technology assets in December 1997.

Following this transaction, Tseng’s management utilized the proceeds from the sale along with existing funds to invest in a start-up company by merging with pharmaceutical firm Cell Pathways in 1998. Cell Pathways was subsequently acquired by OSI Pharmaceuticals in 2003.