Pentium D Refurbished systems going for $245

adding windows 7 to any machine adds about $75 to the value of a machine. I am currently working on my microsoft registered refurb cert. Matter of fact all i need to do is get a tax license and I am in. Anyone can do it. Then you have to buy the windows disk packs from a wholeseller at about $35 a copy. I was thinking of doing it just for a few machines for ebay sales to try and up profits. Not sure I want to though cause then your the tech support. With that being said i just sold some dell optiplex 760 machines USFF with 4gb ram and 80gb hard drives for $95 each with no OS. Dell Optiplex 760 USFF Core 2 Duo E8500 3 16GHz 4GB DDR2 80GB HDD DVDRW AC Power | eBay i have 6 and have sold 4. so why anyone would pay 245 fore a pentium d machine when the can get a core 2 for less than half is beyond me