U won't earn much cpu mining on ur desktop, much lesser on azure, even mining a cpu coin thats new will not earn u much profit.
I was mining Primecoins (XPM) with azure and mined around 2500 coins with 80 accounts (20 core/account) in a period of 2 weeks.
current worth of XPM is 0.005 BTC and it was way more profit as compared to my investment.
People simply use a prepaid credit card that contains no money, azure doesn't care how many accounts u use the same credit card on, this means creating new emails and simply reusing the empty credit card and u have unlimited trials
NO YOU CANNOT SIGNUP FOR AZURE WITH EMPTY PREPAID CREDIT CARDS.
you sound like you don't have any idea how azure works and you look like you are not the most genious of us all.