MSFt decided at the end making a loan to Del and not participateing into any equilty stake. So, the money will be returned with interest in certain years. MSFT's 70$ billionsof cash currently makiong close to zero inetrest. With the Dell loan, msft probably makes close to 5%, so all shall work out good for msft.
With a good relationship with Dell, MSFt will be able to develop all kindsof products with Dell that will enormerously benefit the WIndows ecosystm. SO, for MSFt is a great move!