Background. All tasks for maintaining the integrity of the signal fall on both the circuit engineer and the tracer of the printed circuit assembly. The task of the circuit engineer in solving the problem of signal integrity is to know the limitations of the high-speed interface. The task of the tracer is to know and follow the rules for designing high-speed devices. For the design of printed circuit assemblies, there are currently a huge variety of software packages. It is obvious that the new tasks that faced the designers of printed circuit boards could not but be reflected in the development of CAD. Materials and methods. If in the early stages the use of CAD for PCB design was limited to topological tasks and technological support, then as the problems of ensuring signal integrity and EMC became more relevant, leading CAD manufacturers began to include certain procedures and subsystems in their products. The beginning of 2023 was marked by the release of a number of new versions of popular PCB design systems. Some of them have undergone minor changes, some have been completely updated, but all, without exception, have expanded their capabilities in the direction of signal integrity and EMC. Results. Various electrophysical parameters of printed wiring, the effects of which negatively affect the integrity of the signal, lead to the fact that the process of designing the board and the printed circuit assembly becomes iterative. Even when using a virtual prototype, a physical prototype is needed, after testing which certain changes are made to it. Conclusions. The presence of a virtual prototype reduces the time and cost of design, but it is possible to completely eliminate all the shortcomings only when testing a real design.