I am going to be upgrading my system and am looking for recommendations on minimum/maximum resources to consider in purchasing a new machine. i'll be buying a 27 IMAC with 5Kmonitor, and also have two side monitors. I am an accountant needing to run a variety of tax, time and billing/CMS and other software on the Windows platform. I have also historically run Outlook on the Windows side since the Windows version is better than Mac (not sure about new Mac version). What is minimum amount of RAM I should buy, and is there a maximum amount beyond which it won't help me in anyway? Is there an ideal configuration? Likewise, will an upgraded video card provide any benefit? I assume my choice of SSD versus of Fusion drive has no bearing on Parallels performance? Thank you for any suggestions you have.