The subject is complex and has been explained to death, but I’ll try to simplify. (see link at the bottom)
-How much soundcard participate creating sound in Renoise?
A modernsoundcard does not perform any processing of effects, instruments, anything like that and that is where almost all of the processing goes to.
-Does Renoise really support multicore prosessors or does the prosessor need Hyper-Threadin to renoise really use all 4 cores as should?
Multiple cores/threading means that multiple processes can be run at the same time in parallel. Therefore it’s up to the developer of the plugin to decide if it uses multiple cores or not. (can be ticked on an off for a plugin in renoise). To increase parallel processing you need to increase the amount of independently running signals in parallel. 2 independent tracks with 2 different instruments playing on them are run in parallel, but for example, if youuse a send device to send the signal to another track, you will not be running the 2 tracks in parallel, as the result of one track depends on the result of the other track.
-when i play song window10 task manager says renoise use only 3.5% of all the power it has but renoises use 40% on his own prosessor usage ?
https://forum.renoise.com/t/multicore-faq/19732
Post your config.xml though
Main menu>Help>Show preferences folder