The explorer windows began to flicker and the font changed, what is it?

Question

Windows

Explorer, files, folders were opened. Then the windows became visible in pieces, sometimes not visible. Everything began to languish. Then the font changed to some other.
Launched total commander, virtualka. in parallel, the virtulka was also running.
Closed all windows, killed the explorer process 3 pieces, restarted. everything seemed to be lost.
Could it be because of the lack of RAM, and so everything hangs, changes. I doubt that the viruses did not download anything and there are no left processes in the processes.
Can the exlpore exe restart several times if it freezes and the poetmou 3 processes in the task bar hung.

Answer 1

In the seven, it often happens to me when too many windows are open. Not due to lack of RAM or hardware, something to do with the windows system itself. I close some Notepad ++ and everything becomes ok. Upgrading to Win8 and above may resolve the issue.