Techtool Pro’s Protogo tool is useful for creating a dedicated diagnostic device that you can use to start up your Mac (and other Macs compatible with your OS) for troubleshooting and repair. To get the most out of your Protogo device, it is important that you choose the right drive.
The faster the drive you use for your Protogo device, the better your experience will be. For the absolute best results, use an external SSD connected via Thunderbolt or USB 3.1. If you are using a thumb drive, they vary very widely in terms of performance. In our experience, the very best performers (which can still be found for less than $20) are those which utilize a small SSD inside the thumb drive. Some such examples can be found here. At the minimum, it is best to use USB 3 or 3.1 USB sticks, even on USB 2 equipped Macs, because the memory they use is still faster when connected via USB 2. (And many USB 2 devices use memory that is much slower than the connection itself.)
Once you have chosen a drive to use, creating a Protogo device is simple. You can launch the Protogo window either from the Mode menu or by selecting the Protogo tool and clicking “Open Techtool Protogo.” Once in the Protogo window, select your device, and your profile (we recommend the Basic Profile in most cases), and click Build Techtool Protogo Device.
Pro Tip: If you find that it takes more than an hour to create the device, you may need a faster drive, or you’ll need extra patience while using it as a startup disk. A good target drive speed should be at least 70 MB/s (read and write) for reasonable performance.