In a video with Dave’s Garage, veteran Windows developer Raymond Chen revealed how Microsoft tested Windows 98 to see if and how well it could handle many plugged-in USB devices. USB was something new back then, so the Windows 98 developers first had to gain experience with it.
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The Windows developers used the “USB Cart of Death” for the tests. This USB wagon of death didn’t kill people, it killed many Windows builds. Because it often led to a blue screen on the checked Windows computer. The corresponding build was then completed and needed to be improved.
There were 64 USB devices on the USB cart of death. At that time, that was the maximum number of USB devices that could be connected to a Windows computer (the value is now 127). The Windows developers had packed all kinds of USB devices on the cart (one of those mail carts that you use to pick up and deliver mail in your company), keyboards, mice, printers and even a USB gaming steering wheel with which the The car was then steered. All of these devices were connected to the Windows PC under test via a single USB cable. This was made possible by the Windows developers using many USB hubs connected in series in order to be able to connect the many devices.
This car was driven from Windows developer to Windows developer and plugged into their PCs. As soon as Windows had recognized all devices, the developers tested whether, for example, the connected USB keyboard worked. Or whether the gaming steering wheel worked correctly in the game.
A particularly tough test was to connect the devices, watch as Windows deregistered all 64 devices and activated the drivers – and then unplugged them again. This usually led to a blue screen on the Windows PC. And then you moved on with the USB carriage of death to the next Windows computer. The developer who was working on the crashed PC now looked for the cause of the crash and adapted the Windows source code accordingly. Until the USB car of death next showed up at his doorstep.
The goal was: You should be able to connect and disconnect USB devices as often as you wanted during operation: Windows should not crash, but should continue to run stably.
