Though this topic present over different forums with different confusing discussion but I couldn’t find any instance of it present over here at StackOverflow and it could be
You cannot use Windows Phone 8 emulator on such machine, that's a fact, but you still can develop and test your WP7 apps using the Windows Phone 7 emulator or you can debug on actual devices.
So if you really want to develop Windows Phone apps, try developing for WP7 first and after you get some money, buy real WP8 device like HTC 8S and start testing on in, you don't need new $1000+ development machine for creating great apps!