KB10015: Tandy PC-Compatible Models Compared – 1000 Series through 4000

Tandy Corporation produced a wide range of IBM PC-compatible computers sold exclusively through Radio Shack stores from 1984 into the early 1990s. The Tandy 1000 series is the best-known family, valued today for its enhanced graphics and sound capabilities that made it the de facto standard for PC gaming in the late 1980s. Tandy also produced the business-oriented 3000 and 4000 lines. This article covers every major model in the PC-compatible Tandy lineup.

What Made Tandy PCs Special: Tandy Graphics and Sound

Before covering individual models, it's important to understand the two features that set Tandy PCs apart from generic IBM clones.

Tandy Graphics (TGA)

The Tandy Graphics Adapter was derived from IBM's PCjr Video Gate Array. Where standard CGA could only display 4 colors at 320×200, Tandy/PCjr graphics supported 16 simultaneous colors at 320×200, plus additional modes including 160×200 with 16 colors and 640×200 in 2 or 4 colors. The TGA used a Motorola MC6845 CRT controller and mapped its video memory into a dedicated 16 KB region. Because the PCjr was a commercial flop but the Tandy 1000 was enormously popular, game developers targeted "Tandy graphics" as their 16-color standard throughout the late 1980s. Later models introduced TGA-II, which added 640×200 in 16 colors. Tandy graphics were eventually superseded by EGA and VGA in the industry, and the final Tandy 1000 models shipped with standard VGA instead.

Tandy Sound

All Tandy 1000 models included a Texas Instruments SN76489 sound chip (or compatible) providing three square-wave voices plus a noise channel—identical to the PCjr's sound hardware. This was a significant upgrade over the single-voice PC speaker found in standard IBM compatibles. Hundreds of DOS games included "Tandy/PCjr" sound as an option alongside PC speaker and AdLib/Sound Blaster. The third-generation models (SL, TL, and their successors) added an 8-bit DAC with DMA support, enabling digital audio playback and recording at rates up to 48 kHz—capabilities similar to Creative Labs' Sound Blaster, but built into the motherboard.

First Generation (1984–1985)

Tandy 1000 (1984)

The original Tandy 1000 was conceived as a superior alternative to the IBM PCjr and launched in November 1984 at $1,199. It used an Intel 8088 CPU at 4.77 MHz with 128 KB of RAM (expandable to 640 KB). Storage was a single 5.25-inch 360 KB floppy drive. It had five ISA expansion slots (three full-size, two short), a built-in Tandy graphics adapter, three-voice Tandy sound, and two joystick ports. Unlike the PCjr's problematic chiclet keyboard and sidecar expansion, the Tandy 1000 had a proper keyboard and standard ISA slots, making it both more usable and more expandable. It ran MS-DOS and was broadly compatible with IBM PC software while also supporting the enhanced PCjr graphics and sound modes that most PC clones could not.

Tandy 1000A (1985)

A minor revision of the original with a math co-processor socket (for the Intel 8087) and small motherboard refinements. Specifications were otherwise identical to the original 1000. The 1000A was quickly superseded by the second-generation models.

Second Generation (1986–1987)

Tandy 1000 EX (1986)

The EX was a compact, affordable model aimed at the home market, priced at $799. It used an Intel 8088-2 at 7.16 MHz (a notable speed increase over the first generation's 4.77 MHz) with 256 KB of RAM expandable to 640 KB. It had a single 5.25-inch 360 KB floppy drive built into the right side of the unit. The case was an all-in-one keyboard-and-computer design similar in concept to the Commodore 64 or Amiga 500. Instead of ISA slots, the EX used proprietary "PLUS" expansion cards that slid in from the sides of the unit—a cost-saving measure that limited its expandability compared to the full-size models.

Tandy 1000 SX (1986)

The SX was the enthusiast model at $1,199. It ran an Intel 8088 at 7.16 MHz with 384 KB of RAM (expandable to 640 KB) and two 5.25-inch floppy drives. It retained five standard ISA expansion slots, making it much more expandable than the EX. The SX was a popular choice for users who wanted the full Tandy graphics and sound experience with room for add-in cards like hard drive controllers, memory expansion, and modems.

Tandy 1000 HX (1987)

The HX was an updated version of the EX's compact form factor at $699. It used the same 8088-2 at 7.16 MHz with 256 KB of RAM, but switched to a 3.5-inch 720 KB floppy drive—one of the first PC-compatibles to adopt the smaller format as standard. Its headline feature was MS-DOS 2.11 built into ROM, enabling instant boot without a DOS floppy. The HX used PLUS expansion slots like the EX. A 5.25-inch external floppy drive was available as an accessory.

Tandy 1000 TX (1987)

The TX was a major step up, featuring an Intel 80286 processor at 8 MHz—the first Tandy 1000 with a 286. It shipped with 640 KB of RAM (expandable to 768 KB on the motherboard) and a 3.5-inch 720 KB floppy drive. It had five ISA expansion slots. The 286 processor provided a significant performance boost over the 8088 models, making it better suited for productivity software alongside gaming. Despite the faster CPU, it maintained full backward compatibility with Tandy 1000 software and the TGA/sound hardware.

Third Generation (1988–1993)

The third generation introduced the TGA-II graphics upgrade (640×200 in 16 colors) and, on most models, an 8-bit DAC for digital audio alongside the traditional three-voice sound chip.

Tandy 1000 SL (1988)

The SL used an Intel 8086 at 8 MHz with 384 KB of RAM (expandable to 640 KB) and a 5.25-inch 360 KB floppy drive, priced at $899. It introduced the DAC digital sound hardware and TGA-II graphics. Five ISA expansion slots maintained expandability. The 8086 was functionally equivalent to the 8088 but with a 16-bit external data bus, providing modest performance gains.

Tandy 1000 SL/2 (1989)

A minor update to the SL that bumped RAM to 512 KB standard and included a 3.5-inch 720 KB floppy drive instead of the 5.25-inch unit.

Tandy 1000 TL (1988)

The TL was the premium third-generation model at $1,299. It used an Intel 80286 at 8 MHz with 640 KB of RAM (expandable to 768 KB) and a 3.5-inch 720 KB floppy drive. Like the SL, it featured TGA-II graphics and the new DAC sound hardware, but added an analog-to-digital converter (ADC) for sound recording capability. It also included DeskMate, Tandy's graphical productivity suite, which was bundled with a sound editor that could record and edit audio using the built-in hardware. Five ISA expansion slots were standard.

Tandy 1000 TL/2 (1989)

An updated TL with 640 KB of RAM, a 3.5-inch 720 KB floppy drive, and DeskMate 3.0. Minor motherboard refinements but architecturally identical to the TL.

Tandy 1000 TL/3 (1990)

Further refined with a 10 MHz 80286 processor and 1 MB of RAM, moving toward the specifications that would appear in the 2500 series.

Tandy 1000 RL (1991)

A budget model at $599 with an Intel 8086 at 9.54 MHz, 512 KB of RAM, and a 3.5-inch 720 KB floppy drive. The RL shipped with DeskMate in ROM and included Tandy TGA-II graphics and DAC sound. Designed as an entry-level home PC, it used proprietary PLUS expansion slots rather than ISA.

Tandy 1000 RLX (1991)

An upgraded RL at $799 with an Intel 80286 at 10 MHz, 1 MB of RAM, and a 3.5-inch 1.44 MB high-density floppy drive. Crucially, the RLX moved to standard VGA graphics (640×480, 256 colors), dropping the legacy Tandy TGA in favor of industry-standard video. This marked the transition point where Tandy PCs became more conventional IBM compatibles. The RLX-HD variant added a 20 MB hard drive.

Tandy 1000 RSX (1992)

The most powerful and final Tandy 1000, the RSX used an Intel 80386SX at 25 MHz with 1 MB of RAM (expandable to 9 MB), a 3.5-inch 1.44 MB floppy, and a 52 MB hard drive, priced at $999. It included VGA graphics and the Tandy DAC sound. Three ISA expansion slots provided reasonable expandability. The RSX was competitive with other 386SX machines of its era but by 1992 the Tandy brand advantage had largely evaporated as Sound Blaster cards and VGA had become universal standards.

Tandy 2500 Series

Tandy 2500 XL (1991)

The 2500 XL bridged the gap between the 1000 series and Tandy's business-oriented models. It used an Intel 80286 at 10 MHz with 1 MB of RAM, a 3.5-inch 1.44 MB floppy, and a 52 MB hard drive at $1,499. It featured VGA graphics and still included Tandy sound compatibility. The 2500 XL was aimed at home and small-office users who wanted a step up from the 1000 series.

Tandy 2500 SX/25 and RSX

Later 2500 models moved to Intel 80386SX processors at 25 MHz with VGA graphics, larger hard drives, and 1–5 MB of RAM. The 2500 RSX included a full-height tower case with a 100 MB hard drive. These were competent 386 workstations but no longer carried the unique Tandy graphics heritage.

Tandy 3000 Series (1986)

The Tandy 3000 was a straightforward IBM PC/AT clone targeted at business users. It used an Intel 80286 at 8 MHz (a 3000 HL variant ran at 10 MHz) with 512 KB of RAM expandable to 640 KB on the motherboard (up to 12 MB with expansion cards). It had ten expansion slots (seven 16-bit AT-compatible and three 8-bit XT-compatible), three drive bays, and a 1.2 MB 5.25-inch floppy drive. Unlike the 1000 series, the 3000 did not include Tandy graphics or sound—it used standard CGA, EGA, or VGA adapters in expansion slots. It ran MS-DOS 3.2 and could also run Xenix (Microsoft's Unix variant). The 3000 NL was a later diskless network workstation variant.

Tandy 4000 Series (1988–1990)

The 4000 series represented Tandy's high-end business line with Intel 80386 processors. The original Tandy 4000 used a 386DX at 16 MHz. The 4000 SX used a 386SX at 16 MHz as a more affordable entry point. The top-of-the-line 4000 LX ran a 386DX at 33 MHz and was priced at $5,999, aimed at power users running CAD, multi-user systems, and early Windows environments. All 4000 models were standard AT-class machines with ISA slots and no Tandy-specific graphics or sound—they competed directly with Compaq, Dell, and other business PC makers of the era.

Quick Comparison Table

Model	Year	CPU	Speed	Base RAM	Graphics	Tandy Sound	Price
1000	1984	8088	4.77 MHz	128 KB	TGA	3-voice	$1,199
1000 EX	1986	8088-2	7.16 MHz	256 KB	TGA	3-voice	$799
1000 SX	1986	8088	7.16 MHz	384 KB	TGA	3-voice	$1,199
1000 HX	1987	8088-2	7.16 MHz	256 KB	TGA	3-voice	$699
1000 TX	1987	80286	8 MHz	640 KB	TGA	3-voice	$1,199
1000 SL	1988	8086	8 MHz	384 KB	TGA-II	3-voice + DAC	$899
1000 TL	1988	80286	8 MHz	640 KB	TGA-II	3-voice + DAC	$1,299
1000 RL	1991	8086	9.54 MHz	512 KB	TGA-II	3-voice + DAC	$599
1000 RLX	1991	80286	10 MHz	1 MB	VGA	3-voice + DAC	$799
1000 RSX	1992	386SX	25 MHz	1 MB	VGA	3-voice + DAC	$999
2500 XL	1991	80286	10 MHz	1 MB	VGA	Compatible	$1,499
3000	1986	80286	8 MHz	512 KB	Standard (CGA/EGA)	No	$2,599
4000	1988	386DX	16 MHz	1 MB	Standard (EGA/VGA)	No	$3,599
4000 LX	1990	386DX	33 MHz	2 MB	VGA	No	$5,999

Why Tandy PCs Matter for DOS Gaming

The Tandy 1000 series holds a unique place in PC gaming history. Between roughly 1984 and 1990, a huge number of DOS games supported "Tandy/PCjr" as a distinct graphics and sound mode. This was the only way to get 16-color graphics and 3-voice sound from a PC-compatible without purchasing separate EGA and sound cards. Games like King's Quest, Maniac Mansion, and many Sierra and LucasArts titles looked and sounded dramatically better on a Tandy 1000 compared to a standard CGA PC with a beeper speaker. For collectors interested in experiencing DOS games as they were intended during this era, a second-generation Tandy 1000 (SX or TX) or third-generation model (SL or TL) provides the most authentic experience.

Collector and Restoration Notes

First-generation Tandy 1000 units can develop issues with their power supplies and should be tested before use. The compact EX and HX models are popular with collectors for their small footprint, but the proprietary PLUS expansion slots severely limit upgrade options compared to the ISA-equipped models. The SL and TL models are considered the sweet spot for Tandy gaming because they combine the best Tandy graphics (TGA-II) and sound (3-voice plus DAC) with reasonable processing power. On all models, the internal speaker and audio amplifier circuitry can develop noise or hum; recapping the audio section often helps. The Tandy-specific DIN video connector requires a Tandy-compatible RGB monitor (like the CM-5 or CM-11) for the best display quality, although adapters and SCART solutions exist. By the RLX and RSX generation, the machines are standard VGA PCs and can use any VGA monitor. The 3000 and 4000 series are straightforward AT-class machines and share the same restoration considerations as other 286/386 PCs of their era—CMOS battery replacement, drive belt inspection, and electrolytic capacitor checking.