How many minutes after starting/turning on the PC does Avast Free look for new virus definitions updates?
I don't believe there is a set figure but it is meant to happen soon after the system start, as it may depend on a number of things system load, etc. Since I rarely do system restarts on this laptop it isn't something that worry about.
I very, very long time ago (way back many, many years ago) there was a way to delay this - I have no idea if this is even possible or necessary now (.ini file and or location, plus self-defence module).
intsup.exe - this is the avast installation and update process - it runs very early on and does consume CPU activity as it checks for updates and applies them. Once this is complete it closes.
I have delayed the instup.exe update function to start 5 minutes after boot, by modifying the avast5.ini file.
For a start you could try this, though it shouldn't give that much relief - avastUI > Settings > Troubleshooting and enable the Load Avast services only after loading other system services.
I would warn against doing such modifications even if still possible (different file name and update process) users own risk.
