@Aristarcus86 Hi, and welcome to the forum !
I've taken note of your report, and I'm sorry to hear that crashes at the end of the first round in Rainbow Six: Siege are impacting your experience !
In order to isolate the Issue and in addition to the steps already performed on your end, I invite you to provide us with the following information :
Does the problem persist after checking the steps of our dedicated PC troubleshooting guide ?
It helps solve most of the problems encountered on that platform, and it is an integral part of our investigation.
Should the Issue persist afterwards, or if you have questions, don't hesitate to reach out !