In the 1980s, an IBM computer wasn't considered 100 percent compatible unless it could run Microsoft Flight Simulator.
The Video Game That Defined PC Compatibility
Before "gaming PC" became a marketing term, there was a video game so demanding that it literally defined what a real computer was. In the wild west of 1980s computing, Microsoft Flight Simulator wasn't just entertainment—it was the ultimate hardware stress test.
When IBM released the PC in 1981, it inadvertently created a gold rush. Dozens of companies scrambled to build "IBM compatible" machines, hoping to cash in on the booming business market. But here's the problem: compatible didn't always mean actually compatible.
The Clone Wars
These knockoff PCs were everywhere by 1983—cheaper alternatives promising to run the same software as Big Blue's machine. Retailers stacked them high, slapped "IBM Compatible" stickers on the boxes, and hoped nobody would notice when Lotus 1-2-3 crashed or WordPerfect displayed garbage characters.
Customers noticed. So did the tech press. Someone needed to separate the wheat from the chaff.
Enter Bruce Artwick's Creation
Microsoft Flight Simulator, originally developed by Bruce Artwick's subLOGIC, arrived on the IBM PC in 1982. Written almost entirely in assembly language, it pushed early hardware to its absolute limits:
- Real-time 3D graphics rendered entirely by the CPU
- Complex physics calculations simulating actual aerodynamics
- Direct hardware access bypassing slow DOS routines
- Precise timing requirements that exposed subtle incompatibilities
The program was so demanding that it essentially X-rayed a computer's soul. If a clone had cut corners anywhere—slightly different timing, imperfect BIOS implementation, cheap graphics adapter—Flight Simulator would expose it immediately.
The Unofficial Standard
By 1984, an informal two-part test emerged in the industry. If your "IBM compatible" could run both Lotus 1-2-3 (for business software compatibility) and Microsoft Flight Simulator (for graphics and hardware compatibility), it was the real deal. Manufacturers began specifically advertising their ability to pass these tests.
Compaq famously discovered during development of their portable that Flight Simulator wouldn't run. The culprit? What Artwick described as "a bug in one of Intel's chips." To achieve true compatibility, Compaq had to make their machine bug-compatible—replicating even Intel's hardware flaws.
Bruce Artwick later recalled the irony: clone manufacturers and graphics card companies used his game to verify their hardware worked correctly, "thus saving me the trouble of having to make it work on their hardware."
Legacy
This accidental role made Flight Simulator one of the longest-running software franchises in history. The same meticulous attention to hardware that made it a compatibility test also made it beloved by aviation enthusiasts. Microsoft continued the series for four decades, with the 2020 edition pushing modern hardware just as hard as the 1982 version pushed those early PCs.
The next time someone brags about their gaming rig's benchmarks, remember: the original benchmark was a Cessna 182 rendered in four colors, proving once and for all whether your computer was the real thing.