use run in the start menu and click browse, navigate to where you extracted prime95 to. run it. open run again and find the entry that has the location of prime 95 and add " -A1" to the end of it, including a space and excluding the quotation marks. run that command and you can run two instances of prime95. click options/affinity and change one of them to core 0 and the other core 1. i have a feeling it may fail running two instances of prime.